In Injustice my main is either GL or, recently, Doomsday. With GL I like being able to zone (if completely necessary) and get in easily. Usually I play beat down, like I do with Doomsday. Lots of combos for me. Don't wanna zone. So who would a good character be for me?
Johnny Cage is pure rush down. His projectiles are good, but not for throwing full screen. His ex low forceball is really positive on block so you use it for a frame trap.
Kabal by no means what so ever has to zone, but he has amazing zoning. His Nomad dash pressure is simply amazing. His number of options are insane, however his execution is truly hard, and 1 slip up canceling your nomad dash and you are full combod.
Liu Kang is the character I recommend to all new players. He has great rushdown, mixups, good zoning and decent damage. His execution is easy, but at the same time will teach you very essential skills such as dashing in combos. He has a stance that provides mixups and launchers, a nice number of strings and special moves, instant air fireball. essentially what I am trying to say is that Liu Kang is the Jack of all trades character, playing him will help you learn the mechanics of the game better.