After seriously putting some time into League Play, I have the following suggestions (in order of importance):
1) Please use a competitive ruleset for the Champions Series playlist.
2) Prevent the host on the other team from giving your team the loss purely by dashboarding.
3) Put the highest league somewhere in the combat record. Some people won't want to take a hit in their personal stats if others can't even see the league they are in.
4) More XP should be awarded for the winning team. One of the biggest problems with getting people to play League Play right now is that everyone is in a race to level up.
5) Give the option for the players of a team to unanimously vote to forfeit the match. Whenever you are stomping a team and 3 of the guys leave, it becomes a very boring 4v1 match. This happens frequently whenever you are playing your placement matches with a new team. That 1 guy doesn't want to leave because he will be punished for leaving a game early. But at that same time, he would probably accept a forfeit so that he didn't waste everyone's time.
I realize that some people here may not understand why (1) is important, so let that one be. Please discuss 2-5.