I could list so many... going to try and limit it to ten....
Superman
John Constantine
Wonder Woman
Batman
Powergirl
Dark Sied
Lobo
Klarion
Luthor
The Ultra-Humanite
Best Newcomer : Jon Kent
Honorable Mentions
The Endless
Captain Marvel
Swamp Thing
Every Batman Villain
John Jones
Kid Eternity
Sinestro
Brainiac
Big Barda
Grayson...
Well an more.. DC is so awesome you can not throw a dart with out hitting an awesome character in the face!