For better or worse, he's one on the main villains of the prequels. He's the main villain in TPM and secondary villain in both follow ups. He has more screen time than most Star Wars villains. Also, as much as the films bother me, the designs for the Trade Federation ships/droids/Nemoidians, are among my favourite SW designs. Had the same designs been used in a better film we'd all love them.
You got to love him. He's always yelling for Padme's head.
I'd like him reclining in his walking-chair. "Take-a them away." His TPM appearance was his best outfit.