dsatow

Although it unfortunately never got released for 6th Ed, the Ultimate Vehicle for 5th edition has a lot of extra vehicle combat stuff that might be helpful to make the combat driving more interesting and would be easily adaptable to 6th ed. 
 
But as to your question, I think since vehicle combat, driving and stunts are going to be such a major part of the game you should use Hero to create what you want to see/experience. 
 
Maybe create some new skills like: Vehicle Stunts, Fast Driving, Fast Turns, Vehicle Jumps, Off Road, Chasing (both to follow someone and lose someone following them), Etc... And the players have to buy all these skills and they can by levels in each of them to start and as they progress. This will allow some of them to specialize in different aspects of driving and use them to their advantage. And make things different and challenging in situations. Maybe keep Combat Driving as the "control skill" (so no one can have any of the sub-skills higher then their Combat Driving skill) and they roll Combat Driving either only in situations where no other skill might apply or as a complementary skill roll to the other rolls in special situations. 
 
And then maybe modify some of the other skills to be driving related. For example, allow the Teamwork Skill to be used in driving to coordinate special stunts (two cars towing a giant safe down a city street and working together to use it to take out the cars chasing them, or one car spinning and facing the other teammates car coming up behind them, and using their car as a ramp so the teammates car can use the "ramp car" to make a jump, or when a passenger has to jump from one car to the other) 
 
You can make some Talents like: Damaged Driver (gives penalty skill levels when driving a damaged car), or modify Deadly Blow so that it makes the car do extra damage when ramming another vehicle. 
 
Some powers might be: Hood Holding (Clinging, but only for staying atop a moving vehicle), Drive Thru (Tunneling but only for driving car car through a wall or building without taking damage), Slow Down (Drain vehicle movement but only by hitting the other car first), Smoke Screen (Darkness, but only by spinning the wheels of the car and burning the rubber).
 
This is all off the top of my head, but you get the idea. There could/can be tons of great ways to build up and make a game like this really fun and cool, including adding in maneuvers and driving martial Arts like dmjalund suggests. 
 
 

Have driving based maneuvers and "Martial Arts" so different drivers can have different driving styles

IMO shape change only changes your shape. At the basic level, you don't turn into a fly; you become fly-shaped. Shrinking may allow you to become fly-sized and flight may allow you to fly, but you still don't look like an actual fly.in fact, the difference between you and an actual fly is a Special Effect unique enough to identify that it is actually you. E.g. Beast boy can change his shape and size into any animal, but they are all a very distinctive shade of green.

A common favorite is "Not in the face!" or "Delay!".
 
Hrmmm, maybe I should make a speedster name Dee Lay, so when a tank yells out to Delay, he get a boost to his Ego!
 

It doesn't matter, the character only knows they have successfully hit once and the activation roll makes them believe they can hit a couple more times.  The player may know how well they hit by how well they hit, but the character really doesn't know they rolled.  So the trigger activates on any hit with an 11- or less chance to activate.

For a little while, one of my groups was "Call the lawyers!"

For a little while, one of my groups was "Call the lawyers!"

As GM, you control the game pace.  In this case, it's not about Kryptonite or specialty attack, but just a common attack type.
 
1) If a player has a high level block and trigger attack linked to it, why wouldn't some of the villains?  What will happen is that in one phase, you will get a person blocking and riposting which in turn gets blocked and riposted until one of them fails.  Remember, anything you allow the players to buy, you should be able to buy for the NPCs.
2) Ranged beats HTH in real life which is why the army is equipped with guns and not two handed swords.  Even in fantasy, a quick drawn thrown dagger spoils a fencers actions time and time again in movies.  If your city guards only have swords, then your city guard is poorly armed.  I would equip them with crossbows and have swords as back up weapons.
 

I can see his nickname on the street as "Flatfoot" 🤣
 
Any idea of the power level you looking at (8DC, 10DC, 12DC, 14DC)?
 
I can see growth stats and maybe 3 levels of damage negation.
A couple of PD/ED worth of resistant protection as toughness.
A slight advantage in HTH OCV.
Possibly claws and bonuses to climbing.
A tiny little police pistol and the other standard equipment of police officers.
Distinctive features.
A psychological love of donuts, coffee, and beef jerky (Jack Links!)
 

The solution is using ranged attack.

Just my $0.02.
 
Personally, I think it's a matter if the player can decide whether to use a power that is at the issue.  If the player does not have a choice (i.e. that choice is preprogrammed into the trigger), then the action can occur during another action.  If the player can choose what to do with the action, then it can not occur in the same segment as another of the player's actions.
 
Example: A trigger for a land mine would allow two attack actions in a single segment by the player because the player does not control the action of the land mine.
Example: A player covering a target would only get their action or the cover damage, because the player can choose to release the cover.
 

As GM, you control the game pace.  In this case, it's not about Kryptonite or specialty attack, but just a common attack type.
 
1) If a player has a high level block and trigger attack linked to it, why wouldn't some of the villains?  What will happen is that in one phase, you will get a person blocking and riposting which in turn gets blocked and riposted until one of them fails.  Remember, anything you allow the players to buy, you should be able to buy for the NPCs.
2) Ranged beats HTH in real life which is why the army is equipped with guns and not two handed swords.  Even in fantasy, a quick drawn thrown dagger spoils a fencers actions time and time again in movies.  If your city guards only have swords, then your city guard is poorly armed.  I would equip them with crossbows and have swords as back up weapons.
 

Cover is not necessarily known by the target.  If the target can see the attacker, it would be obvious that the attacker is covering someone and possibly the target.  But why should the target know they are being covered if there was no power activation and no LOS of the attacker.

In this case, I would rule that the covering character had the option to either roll his cover damage then enter combat normally, or forego his cover damage and enter combat normally, or forego entering combat and maintain his cover. 
 
 

I would probably due as a cumulative mind control along with something else.  This probably isn't what the OP wants which is an all or nothing attack and as Gnome points out HERO makes you pay through the nose for something that as well as most GMs tend to hate those kind of things.

Just my $0.02 disclaimer.
 
I like how pathfinder describes curing disease with remove disease.  The magic removes the disease but does not give immunity to the disease.  So removing disease just means you can be reinfected.  So most powers would probably do this.
 
Another point, if Viper could come up with a deadly virus (say like in Contagion with a high infection rate and a 25% kill rate), a super genius hero could come up with a cure or vaccine.  But to be honest, I don't think most super smart supervillains/organization will use bioweapons like disease.  Germs generally are notorious for mutating and making your vaccine/immunity useless.  About the only group I think willing to use bioweapons is Mechanon who might think a virus is not really a living thing per say.
 
If I were to implement an epidemic plot, I would probably make the disease highly infectious via breath and contact, is slow to develop symptoms (so an infected person could transfer the disease without knowing it) and such that a very healthy person would show no symptoms and be a carrier.  This would make supers who make a Con Roll, not get symptoms but who are carriers unless they have immunity to disease.  I would make the infection based on a Con Roll, if you make it, you wouldn't get symptoms.  If you make it by 5 (or 10 depending on the game), you don't get infected.  If you are sickened, you must make 3 Con Rolls consecutively in 3 days to get better.  You get a +1 for making the previous roll and a -1 for failing a previous roll cumulative.  If you make any of the Con rolls on a success as a 3, you are actually a mutant/mutate and you get better because of the mutation assuming you aren't currently a mutant/mutate.  If you fail any of the Con rolls with an 18, you mutate as a horrible monstrosity, no longer able to fit in at first glance with humanity.  The disease drops your BODY and CON by 1d6-3 each day.  The effect would affect figured stats normally.  The one thing I definitely would not do is stat out the disease.  The disease is what it is.

Just my $0.02 disclaimer.
 
I like how pathfinder describes curing disease with remove disease.  The magic removes the disease but does not give immunity to the disease.  So removing disease just means you can be reinfected.  So most powers would probably do this.
 
Another point, if Viper could come up with a deadly virus (say like in Contagion with a high infection rate and a 25% kill rate), a super genius hero could come up with a cure or vaccine.  But to be honest, I don't think most super smart supervillains/organization will use bioweapons like disease.  Germs generally are notorious for mutating and making your vaccine/immunity useless.  About the only group I think willing to use bioweapons is Mechanon who might think a virus is not really a living thing per say.
 
If I were to implement an epidemic plot, I would probably make the disease highly infectious via breath and contact, is slow to develop symptoms (so an infected person could transfer the disease without knowing it) and such that a very healthy person would show no symptoms and be a carrier.  This would make supers who make a Con Roll, not get symptoms but who are carriers unless they have immunity to disease.  I would make the infection based on a Con Roll, if you make it, you wouldn't get symptoms.  If you make it by 5 (or 10 depending on the game), you don't get infected.  If you are sickened, you must make 3 Con Rolls consecutively in 3 days to get better.  You get a +1 for making the previous roll and a -1 for failing a previous roll cumulative.  If you make any of the Con rolls on a success as a 3, you are actually a mutant/mutate and you get better because of the mutation assuming you aren't currently a mutant/mutate.  If you fail any of the Con rolls with an 18, you mutate as a horrible monstrosity, no longer able to fit in at first glance with humanity.  The disease drops your BODY and CON by 1d6-3 each day.  The effect would affect figured stats normally.  The one thing I definitely would not do is stat out the disease.  The disease is what it is.

Just my $0.02 disclaimer.
 
I like how pathfinder describes curing disease with remove disease.  The magic removes the disease but does not give immunity to the disease.  So removing disease just means you can be reinfected.  So most powers would probably do this.
 
Another point, if Viper could come up with a deadly virus (say like in Contagion with a high infection rate and a 25% kill rate), a super genius hero could come up with a cure or vaccine.  But to be honest, I don't think most super smart supervillains/organization will use bioweapons like disease.  Germs generally are notorious for mutating and making your vaccine/immunity useless.  About the only group I think willing to use bioweapons is Mechanon who might think a virus is not really a living thing per say.
 
If I were to implement an epidemic plot, I would probably make the disease highly infectious via breath and contact, is slow to develop symptoms (so an infected person could transfer the disease without knowing it) and such that a very healthy person would show no symptoms and be a carrier.  This would make supers who make a Con Roll, not get symptoms but who are carriers unless they have immunity to disease.  I would make the infection based on a Con Roll, if you make it, you wouldn't get symptoms.  If you make it by 5 (or 10 depending on the game), you don't get infected.  If you are sickened, you must make 3 Con Rolls consecutively in 3 days to get better.  You get a +1 for making the previous roll and a -1 for failing a previous roll cumulative.  If you make any of the Con rolls on a success as a 3, you are actually a mutant/mutate and you get better because of the mutation assuming you aren't currently a mutant/mutate.  If you fail any of the Con rolls with an 18, you mutate as a horrible monstrosity, no longer able to fit in at first glance with humanity.  The disease drops your BODY and CON by 1d6-3 each day.  The effect would affect figured stats normally.  The one thing I definitely would not do is stat out the disease.  The disease is what it is.

my excuse involved COVID-19

Darkness with personal immunity could work.  The immunity being those with access to a VPN of sorts to the radio communications. Security Systems could also work.  Basically, you use the base's security systems skill roll to encrypt the transmissions.  This has precedence in early Hero supplements. As unclevlad noted.  Barrier can also be used.  Any power which can prevent a sense can be used to block radio reception and personal immunity used as an exception. You could use Clairsentience to go outside the restricted area, but this might be limited to receiving, depending on the GM and special effects.  It also could be blocked depending on the GM and special effects. You could by special effect make the walls lined with copper, or place the base under 6' of concrete.  Communications would then be limited to wired retransmission.  Again, it depends on your GM. You could suppress radio within the area of the base again with personal immunity. That's all I can think of right now.  Probably, the cheapest would be the Security Systems route or using the special effect of the building location/materials.
 

So, I've been online looking at flail fights on youtube.  For the most part, the flail seems to be less used to get around one's shield as to counter people using their weapons to block.  It doesn't seem to be a great weapon compared to a sword but it isn't super bad.  But in comparison with other options, I wouldn't want to use one.
https://www.youtube.com/watch?v=ukvI295xDRw
https://www.youtube.com/watch?v=FWVY3EqU6Ok
https://www.youtube.com/watch?v=haSHLtn-6tE
 
And here's a guy (and he's not the only one) that basically says that the flail isn't the best medieval weapon.
https://www.youtube.com/watch?v=Ox4sCJnCpzo
 
Finally, here's a historian from the Smithsonian.  Not a video but an interesting read.  He believes the flail might be symbolic or even  an experimental weapon which failed.  He does note that two handed flails did exist, but the flail as a one handed weapon probably did not.
https://www.publicmedievalist.com/curious-case-weapon-didnt-exist/

That's too bad, but better to stay safe than sorry.  Hopefully things will quiet down enough in a few month time where a convention can happen again.

Again this build doesn't work the way you think it does.  The difference is where you put the the Usable Simultaneously.  If you put the Usable simultaneously on the personal immunity, then you are transferring the ability of the personal immunity to the recipient but not the darkness power itself.  That power is still with the active user.  Thus if the recipient has the darkness power of up to 40 active points, they could use it for their power, but if they didn't have the power, the naked advantage does not apply.
 
In order for it to work you need to attach the Usable Simultaneously as part of the naked advantage making the power 30 active points.  Naked advantages of Personal Immunity and Usable Simultaneously on 40 active for 20 points.  Reduced End on the Naked Advantage for +1/2 = 30 Active.  IIF on power construct reducing final cost to 24 pts.
 
In all honesty, its a waste of points.  You can put Personal Immunity on the original darkness and then define that the personal immunity is due to special goggles.  Then anyone with the special goggles would be immune.  This could be copied by the villains but they would have to somehow discover this initially before implementing a workaround.

I grew up in Scotland, sunlight was at a premium...