I like to think of Syndrome as the real hero of "The Incredibles" and the Supers as the agents of a cruel heirarchy trying to put everyone in their place.
@DashForever: That didn't matter to him. The problem was that they were still out there, and could still be reactivated. The world could go back to the way it was, and Syndrome didn't want to see that.
@Wind Chaser: I don't think ambition was what made Syndrome fall (morally speaking), so much as hate and revenge. Ambition was there, but if that were everything, then it wouldn't be such a huge problem.