Multiple Queue in Launcher
A lot of people don't care whether they are playing Summoner's Rift, Twisted Treeline or ARAM.
People download League to play, not to sit on the lobby home screen.
Implement a queue system lets you queue up for all three game modes, and whichever pops first is the one you play. You aren't told of the game mode until you enter the lobby to stop people declining when they get a map they don't want.
Simple idea, for the many of us who don't care what we play.