Hi,
Have you guys ever thought about doing a 2 vs 2 queue with rankings? I think that this can only promote the MP aspect of the game. I mean whats better then a victory with your friend by your side or taking them down with you for a crushing defeat?
I know you can do public games, but come on people love rankings 
In the rankings you can team with different people as well but once you have played with that one person once it keeps that score going. For example:
11. TonyJohnMinter + DJRedJoker 1,000
12. Random A + TonyJohnMinter 900
13. Random A + Random B 700