I am a League veteran here, currently sitting at diamond 3 solo queue. I have realized becoming stressful with playing League of Legends. People actually get angry and mean while playing the game. And where is the fun that heals us from anger and meanness? Ultra Rapid Fire gives us laugh and pleasure during the entirety of the game.
If there is a one wish for League of Legends, I would want to make Ultra Rapid Fire a permanent mode.