Im sure they made Iceman's suit fire-resistant for obvious reasons.
Did anyone listen to the X3 commentary? It's a no-brainer why X3 was done very poorly. If FOX waited for Singer... things would have been very different for the better. The movie wouldn't have been rushed and the script would have been a lot more memorable like X2. IMO X2 didn't have that many cheesy lines... if any. Pyro would have had a meaningful role besides being Magneto's lackey. Also there wouldn't have been so many nods to the comics. Not that the nods were a bad thing but it's like the movie revolved around the nods. They were trying to please the comic book fans, maybe I'm wrong... but I don't think it worked and hurt the film significantly.