Make Ascension new Dominion
Dominion has lost so much popularity, but Ascension was Super Fun. I was thinking, ... I know Ascension is a "special" game mode for 2 weeks a year or something, if we even get to see it that often (this year it hasn't happened yet and we're 1/3 through Summer Split).
So.... Ascension should just become the NEW PERMANENT Dominion, bring back the popularity a few notches, and maybe upgrade the map minions/towers/etc like you did for Twisted Treeline.
I think Ascension would really keep the game mode popularity up, make it take less time to wait in queue, and make it even more fun/competitive (not ranked-like competitive, but you know, competitive like FUN).
RIOT, Please Seriously Consider It!