Ladder League: Individual mixed team games
Would it be possible to create something similar to the Dota 2 NEL league (http://neodota.com/nel/) or Dota 2 Ranked Party Matchmaking where you have a standard ladder with each person having an individual ranking, but can put a random team of 5vs5 (for eg.) together and then it adjusts the ELO for all those that took part according to the match win/loss and the ELOs of those that took part.
Currently the only way I can think of doing this is by creating a ladder and creating a match for each person vs each of those in the 5v5. Not only would this be a lot of work, but would be inaccurate as well (With winners/losers ELO adjusting diminishingly to 5 matches instead of 1).