Interesting build there, Chromatic.
I think 18 points is a fair amount for that ability. However, that only comes to 18 points for a Speed 7 character. A speed 10 character would pay only 7! A speed 3 character would be paying 33. And they all get the same result. Yes, the lower Speed character's extra point is slightly more flexible since he has more "open" segments to use it on, but not enough to warrant a 15 point difference. And the Speed 10 and 11 characters get more usefelness than one point of normal Speed, for LESS cost.
I like the idea, but the payment for it is only balanced for a very few Speed numbers.