My suggestions?
My Little Pony: Friendship is Magic (Yeah, yeah I know, just give the first two episodes a watch and see if you like it)
Phineas and Ferb OR Gravity Falls (Two very fun cartoons that don't talk down to the viewers, and on the Disney Channel, no less!)
Avatar: The Last Airbender (Fantastic story, great animation, and set in a whole well-crafted world)
Ventures Brothers OR Harvey Birdman: Attorney at Law (Two very... different look st old-school cartoons)
Scooby-Doo: Mystery Incorporated (This a'int your daddy's Scooby-Doo. This is... well, a different look at the concept)
Samurai Jack OR Megas XLR (a pair of awesome action-based cartoons, one with a great story, the other with lots of humor.)
Adventure Time (Fun and surreal, with a hinting of a darker undertone.)
Enjoy!