Currently, it feels like there's quite a bit of variance in the power of different feat specializations. I'm thinking specifically of weaker feats like Skinner/Clothier, Neurology, Gun Nut, etc., where even a significant point investment may be unnoticeable. Contrast these with any feat that has an action point or cooldown reduction specialization.
I think one potential way to make these specializations more attractive would be to reduce the points necessary to fully specialize - for example, if Skinner had a 4 point specialization with each worth 2.5%, rather than 5 points and 2%. This wouldn't directly increase the power of the feat, but would make actually specializing in it feel less like a trap.