Make games longer again, and make URF a permanent gamemode.
In this way, those truly desiring a faster experience can go to ARAM/TT/URF at their leisure; and the ones of us that love Summoner's Rift and it's fashionable old slower-paced games have our own home as well.
Not sure if URF had bans before, but it'd probably need them then. [slayer-jinx-wink]