So far one of the biggest improvements from MK9 to this is how the air game is going to work. Not going to lie, not a huge fan of MK9s overpowered leap frog crossover JIP nonsense, so I'm very thrilled.
Starting with the obvious, everyone now has different jump arcs, and most of them are pretty big floaty arcs. Everyone also has unique jumping normals, I'm sure most characters will still be able to knockdown from a Jump attack, and start a combo, but what does it will be vastly different between the cast.
Then there is also Down 2, which is basically an Uppercut from MK, except they have way less recovery so you can in fact start a combo from them.
Both anti air specials and anti air moves seem to be much more prevalent in this game, with each character having several.
Superman- Anti air grab, air diving punch, air eye lasers, air dash.
Catwoman- Anti air whip, air whip.
Nightwing- Anti air explosion thing, Air kunai downward.
Batman- Anti air grapple, Anti air batarang, KL spin, anti air bats, dive kick, double jump, cape glide, air explosion thing
Cyborg- anti air fireball, anti air sonic canon, both directly upward, and at an arc, Kabal fireball, downwards fireball, grappling hooks.
Grundy- Anti air grab
Flash- Shoryuken
Harley- Anti air gun shot, Air gun shot.
Green Arrow- Normal arrow can be used at an upward arc, straight up, in the air straight, or downward. Anti air explosive shot, anti air arrow barrage, air arrow barrage.
Wonder Woman- Anti air tiara, KL spin, Shoyuken, air dash, air superman, air tiara, air diving punch.
This is all just what I have gathered from watching off screen videos of terrible people, so I have no idea how it will actually work in practice, but so far I'm a fan.
Not really a whole lot to discuss on the matter, I just find it interesting.