For me I read the clothing part as making it easier to identify the characters when out of uniform. Yes, Storm is striking and you most likely won't miss her. But Cannonball? Havok? Iceman (when they make him blond for whatever reason)? Then you just have confusing blond white guys. Giving them clothes with a color scheme to match their uniforms would help the reader figure out which is which.

I have liked the idea put forth by Jumbo and mutant culture and such as that has very real world connotations.