Re: New Superman Animated Series.
I'd love the idea of another Superman cartoon, however it depends on the audience.
If it's a kid level like say the recently deceased Green Lantern cartoon, then I guess it would be ok to have juvenile villains like Bizarro, or Toyman.(Was never really a big fan of Bizarro). If it's something similar to Young Justice, I'd want better villains.
Villains I'd like to see:
31st Century villains in a Legion of Superheroes story arc
Doomsday(as a season finale villain, which would leave the episode as a cliffhanger to Superman's death)
Superboy-Prime(make him do some sort of retcon punch for giggles)
An epsiode featuring Kryptonite mutants, which pay homage to the freaks of the week from Smallville,