Needed change: Pure MMR Rating for 2s and 3s
Honestly, the need to play like 70 - 100 games just to get to 1500 is such a big turn-off.
Also, if you only play casually it's hard to find mates and play with them consistently. Especially if you are not teamleader you just know that every game you play will be "lost".
Therefore, if start rating=0 stays, I think a huge improvement would be just to have a personal mmr rating for 2s and 3s. Even exactly the same system as SoloQ would work well.
Of course it wont happen since it's not fcking blizzlike but it would be so much better. Peace out.