Suggestion to better the game...
In the event that a player DC's, or quits, I think there should be some kind of a failsafe to ensure the game isn't completely ruined by becoming a 4v5.
Put DC'd player/quitters champion on auto-pilot with a bot, set to a difficulty respective to the rank tier you are in. So, bronze = beginner bot Silver = medium difficulty bot Gold = hard bot. Plat+ = Insane/Doombot quality bots.
Or maybe everyone who ques, should have a backup player to fill a slot that opens up via someone quitting. 5 players, all with someone on the sideline, to join their game...theres no guarantee a player would be available to enter, but the odds aren't bad that your buddy sitting there surfing YouTube would get the call to substitute for a leaver, and join.