I don't know if this has ever been suggested before, but why not allow a system for mods that allow you to veto certain mods, kinda like how you're able to veto maps on Starcraft 2?
Say we had a pool of ABD, TK, Lenshu, Boxshu-Mushu, and Judofrac. If each player was allowed to veto a mod, you would still be left with three mods to play at the very least, and it would also keep more players happy since you would be able to remove your least favorite mod of the five.
Of course, this probably wouldn't work very well in ranked lobbies, but perhaps it could be implemented in a different way by having lobbies separated by the mod that veto'd?