Kitty, Pyro, Iceman and others are there for no reason other than to be there. First, the mutant-making machine. Magneto has a machine that can make a human into a mutant. When Mystique changes form, the CGI people have no idea what mass is. In the comics she could also never have kicked the crap out of Wolverine but she seems to do it with barely any effort in the movie.
Sabertooth is just a big, hairy bum here.
Toad is annoying and really stupid. The fights are so overblown and over the top that they are funny to watch. There is no logic shown in the movie by any of the characters and especially not by the cops. The sets look like something stolen from a James Bond film. The dialogue was awful and really forced.