I suggest kinda Apex Legend ranking system. Even If you lose If you played very good as score/kill/assist you should get +MMR. In this system there is no need to play good or bad, if you win +2 if you lose -8 or even higher. You should give reward to players.
For an example: (Numbers hypothetical)
Normally you should get only for winning +10
5 kill adds +2 and even more +1 by each 5 kills
5 assist adds +2 and even more +1 by each 5 assist
If you make +2000 score you should get +10, and even more +5 for each 500 score after 2k score
@Dejan @badbuckle @Callum