"Open mid" - Ban it
Seriously, to hell with premades wanting to open mid and throw the game because of either their stupid mistakes or just trolling. If you want to quit early, I feel this should be an option strictly for 5-man groups unless the other randoms also all 100% agree to end the game. Just wasted 18 minutes because 3 douche bags decided to intentionally feed. They weren't even that behind, they were like 0/2 or 0/3. So when my friend and I preferred to play at least the next 10 minutes out, they just sat around in the fountain moving their character now and then. And if being AFK is a bannable offense, I don't see why this shouldn't be either.