Green Lantern!
Why?
When I first picked the game up I didn't know who to mess around with. Eventually I found myself caught under his verdant lifestyle. From the balance to the B12 or B13 I really like his play. I play a very aggressive GL and I think it catches people off guard since everyone seems to rely on Lantern's Might too much and that is what people expect. However, I am looking for a strong secondary to get around zoners. GL's dashes don't quite cut it. I spend too much time air turbining around to get from A to B.
That being said my secondary is:
The Flash and Nightwing!
Why?
I love the pressure that the Flash puts on. His mixup game is some fun shit. I really like the speed he plays with. Nightwing as well, but with the secondary option of going on the defensive with dat staff stance. They may not be the best at getting around zoners, but they have options and will surely punish the weak!