I have been thinking about team games for a while and have come up with an idea...
Why not have a team rank? Everybody could register a team and select upto 4 players to join that team. For example, my team would be called "Squad A", I could password protect my team and send invites out for people to join. They would recieve the team name and the password. So in my team as an example I would send out invites to Paulb28, and Nemesischild and we would become Squad A (A triples team)
The team 'principle' or creater would be able to liase with other team players and set-up team games. Instead of having individual ranks, players could have team ranks. Everyone would start at Recruit and build up team points. The team games would have no bearing on the individual rank and vice-versa with single player games.
The team principle would be responsible for starting games, if a team has 4 possible players but only 2 can play, then the creator can set up a 2-player team game.
There could be a team leader board as well as a singles leaderboard.
Just an idea....