I was quite disappointed with Iceman's performance in the movie. Sure, I appreciate the fact that he was even in the movie, but I was expecting more effects with his ice powers. Creating an ice rose, ice wall, and ice skates is cool and all, but the producers should have taken it up another level, and given us fans his ice slide... Even if it was for a brief moment. Hell, the price it took to have Jackman on-screen for 15 minutes could have paid for Iceman's slide alone. I think if Fox had done the movies right from the start, most original five fans would have been okay with that.
And the fact that they could have brought in the third wave of X-Men (Storm, Colossus, Nightcrawler, Sunfire, Thunderbird, Wolverine) in the second film, could have lead to a spectacular 3rd movie. Hopefully, Fox will reboot the franchise with an entirely different (true to the comic book) approach in 10 years or so.
Getting back to Iceman, the final fight in X3 should have shown him doing some hand-to-hand combat movies, not making icewalls to protect himself. That only happened once in the movie, and for the rest of the time, he was no where to be found... Up until the Pyro fight. Whether or not he was hiding, who knows.
And speaking of the Pyro fight, I don't see why Pyro should have ever had the upper hand... Only because they were fighting in an environment with fog and mist all around them. Sure the good guy always prevails, but seeing the situation for what it is, and what Bobby had to work with, Iceman shouldn't have shown any weakness.... period.