Re: commonality of unusual defenses
I think high exotic defenses may be a symptom of a deeper problem. Exotic attacks remind me of the Artful Dodger problem.
For example, consider a Mind Control command to do something reasonable but unproductive, like protecting civilians or attacking a City-of-Heroes-style tanker. You need to win the attack roll, effect roll, and the first breakout roll to have any effect, which is uncommon in my experience. However, if you succeed, you neutralize the foe for a Turn.
A big normal attack can force a couple of lost phases, while the opponent recovers from stunning, takes an extra REC, or moves back into position after knockback. While that's a huge advantage, an opponent can recover and (more importantly) still make significant choices while he's recovering. In contrast, the Mind Control victim is mostly useless for a whole Turn, long enough that the fight is practically over when he finally recovers.
Mind Control isn't too bad if you have a mentalist on your side, because he can spend a phase to cancel the effect. That makes it comparable to spending an extra REC to shrug off a big normal attack. Unfortunately, you're still screwed if the enemy takes out your mentalist first.
Flashes are even nastier. There's no "breakout roll," so it's easier to neutralize a foe, and the main "recovery" action (a non-targeting PER roll) only removes some of the penalties. While you could create a Flash counter similar to the mentalist's override, it's easier to just buy up Flash Defense or buy a redundant targeting sense. This makes Flash a rock-paper-scissors attack, too effective against some foes and useless against others.
Adjustment Powers have similar problems. They can easily adjust you into uselessness, and "recovery" abilities are fairly rare. Negative CSLs are especially bad, roughly equivalent to sight-group Flashes.
In my experience, players feel that exotic attacks are too unreliable, too effective, or both (depending on how often they win the rock-paper-scissors matchups). In my new Champions game, the heroes' powers include Flash, Mind Control, and super Presence. The first two can easily neutralize a foe, but they're unreliable (in different ways: the Flash is rock-paper-scissors, and the Mind Control is like attacking an Artful Dodger). In contrast, the Presence attack (which has no DEF!) seems well-balanced against normal attacks. It's reliable but it only offers a limited combat advantage. So far, the Presence hero seems much happier with her power than the exotic-attacks guy is.
Even though the Flash, the Mind Control, and the Presence attack cost the same amount, the powers are not balanced against each other, for the same reason an Artful Dodger is not balanced against a Brick. I think exotic attacks would be much better-balanced if they had a "recovery" action that cost a phase or two, like normal attacks and Presence attacks do.
For example: In combat, allow a breakout roll vs Mind Control once per phase, as a half-phase action. This means that a successful attack will always have some useful effect; at the very least, it will waste the opponent's time, like a Presence attack. It makes Mind Control more useful for superheroes, and it makes universal Mental Defense much less necessary.