If Reptile is the Dragon King and he is bad then I think Khameleon should return. Frost should be in it instead of Sub-Zero just give her his moves and stuff. Kabal should return. I think that some of themajor characters (Rayden, Jax, Sonya) that have been in just about every game not be in the game. Have some of the least used characters that are cool in it like Sareena, Baraka, Tremor and Ermac (it says he hass a connection with Kenshi) and most people might agree Jade should be in it. She could replace Kitana.

Another thing is there should be a type of Tag Team mode and each character could have a partner in it. For example:

ERMAC/KENSHI:
Both do a telekinetic slam on the opponent

KHAMELEON/REPTILE:
Turn invisible and do a combo on the opponent