I've said it Before, but since Rito has yet to pick up this excellent idea, I'm restating it here.
Give us, the players, a way to reduce the spread of MMR in our opponents. When I que up, I want a way to set the MMR difference of the players I'm going to play with, like +/- 400 MMR.
I am sick and tired of games being a complete waste of time because a Diamond and his bronze friend decide to have a "fun evening". It's no fun for the rest of us. Why not give us an option to play unranked games, but with the teambalance of ranked games? Is that really so hard?
Now go fix this rito, or you will force me to post again...