I hope they avoid having discrepancy between how the characters are portrayed in story mode/intros/outros and their moveset.
Cassie Cage never uses a drone in story, mostly just martial arts and gun kata stuff, which is cool enough. Moveset half-heartedly includes drone, and a major customization option is on the drone which is seldom used.
Sonya the same - never uses drone in story, and barely have any good drone moves but her fatal blow and fatalities emphasize it.
Geras - never uses machete in story or otherwise, suddenly uses a machete in fatal blow.
Jacqui - fights amazing in story mode with her gun fists, but has zero such moves in actual moveset except for shooting a bit her fatal blow. Also, her grenade which blows up into a wall is only used in throw, fatal blow and fatality, why not more focus on this cool gimmick which would make character stand out a bit more. Could be like Urien in SF.
I'm sure I can find several other examples like this - looks like there were different divisions of Netherrealm working of different stuff lacking someone who could have a complete oversight and hold it all together resulting in a pretty fractured experience.
Gear should make sense for all characters. Sub Zero having customizable knives or whatever he never uses etc. etc. feels forced. Small and insignificant gear pieces like that seems like lots of work for NRS for no real value for end product.
Now for gameplay stuff:
Most important: No variations.
Krushing Blows are very cool in concept and partially in execution, but could be toned down a bit. Some characters are all about just going through the motions trying to land their KBs whilst for other characters they are basically a non-factor. Either do them better and fairer, or remove them.
No infinite fatal blow if you spend it you should lose it.
No separate offense/defense meters. Auto-refill I'm fine with.