Erron Black because how badass would that be ? Very badass in my opinion.

Thinking its Cassie as well, she seems to be the poster star of the newbies, just underneath Scorpion and Sub Zero.

Takeda, Jacqui and Kung Jin were introduced too late to be the new head liner.

Takeda (with him being Kenshi's son and Scorpion's pupil) could be a second best, but they need to make sure they don't go full "LOVE THIS CHARACTER, YOU LOVE THIS CHARACTER NOW, WHY DON'T YOU LOVE THIS CHARACTER?" WWE style with Roman Reigns.

Cassie kinda gets away with it (Johnny and Sonya's kid) because she seems a normal-ish and relatable person.

I think there is a chance that evil will beat evil in this one. A betrayal perhaps, results in the death of the boss but brings new evil to power. Then during MK11, the pups will have grown enough and good will prevail again.