1.) Kung Lao
2.) Tanya
3.) Raiden
4.) Quan Chi
5.) D'Vorah
6.) Jax
7.) Shinnok
8.) Cassie Cage
9.) Erron Black
10.) Sonya Blade
11.) Sub-Zero
12.) Kung Jin
13.) Scorpion
14.) Kenshi
15.) Kano
16.) Johnny Cage
17.) Ermac
18.) Kitana
19.) Ferra / Torr
20.) Liu Kang
21.) Kotal Kahn
22.) Reptile
23.) Mileena
24.) Jason
25.) Takeda
26.) Jacqui
27.) Goro
This game is becoming more and more about good normals which I like. Four factors to this:
1) range
2) speed
3) priority
4) multi hitting
Characters IMO with the best buttons based on the above list are:
(in no order)
Lao, Jax, Devorah, Shinnok, Cassie, Cage, Sub, Scorp, Kano, Tanya, Sonya, Erron.
It seems the game has switched slightly from 50/50s to block pressure and chip damage with mixups like Batman in Injustice. They make it a little too easy though with lao's ex hat spin, mournful kitana's ex glave, shoulin ex glave, and tanya ex tonfa. They pretty much give you free pressure and free mixups without the execution. As long as that remains in the game, these characters will continue to move up the list.
Those with good run cancel pressure will also stay relevant. Liu Kang DF, Cage A-list, Scorp hellfire, Jax, and Devorah.
Good 50/50s will keep characters relevant also but placing will be inconsistent.
Unfortunately, if your character isn't one of the ones I listed in the above lists, your probably going to struggle in this game...at least thats my opinion.