MKX is Injustice with faster mobility, better graphics and more safe 50/50s. A lot of people don't want to admit that because it's MKX, the game they've been waiting for for years. LBSH, variations are essentially a character having 3 chances at being good. Most characters have 1 main, another that's MU-specific, and then one awful variation. Maybe this'll change after balance patches but it's gonna be tough for them to balance so many characters.
IMO, Injustice was a great game that was a step in the right direction for NRS. It accompanied many different fighting styles, it was definitely a step in the right direction in terms of balancing (minus a few hiccups), and there was a good balance between offense and defense. If the stages were shorter and walkspeeds were faster it'd be even better but hopefully NRS will incorporate that if they ever make a sequel (which I imagine they will).
The offense in IGAU was crazy due to B2B, but it was balanced by invincible wakeups and good backdashes. In MKX, the setplay is obviously not as wild as IGAU due to the block button, but it's far more intimidating due to shitty defensive options so it's a lot more polarised towards the rushdown side. Zoning is nowhere near as effective as IGAU/MK9 due to the run button which makes matches more linear and boring imo.
I don't like the direction they've taken in terms of pressure. I thought that a Block Button was supposed to take away any crossup shenanigans and add heavy chip damage in it's place - like MK9. Instead they've toned down the chip damage meaning that the only effective way of getting significant damage is with a 50/50 mixup, which, by now, I think we've all noticed are extremely prevalent.
Don't get me wrong, I really like MKX - it's a fun game. The competitive side of it is booming all over the world, which is fucking amazing. But I'm not gonna lie, I'm a little disappointed in the game itself.