A special queue that players can join to try and find a game with an afk, the person queuing up chooses about 3 - 6 champions they dont mind playing and if a person in a game has been afk for more than 10 minutes, than the person in queue can take their place.
The person who took the players place retains the original players runes, masteries, gold, and champion when they join the game, it sliterally just a different person.
Players who join and play these games get 75 - 100% of the ip reward depending on how long they actually spent in the game.
So in practice it would be something like this;
Jinx ragequits and afk's in a game for more than 10 minutes
Bob joins the replacement summoner queue and chooses the champions Graves Jinx and Varus as there preferred champion, there are two games with the champions that Bob wants that are afk so Bob can choose either to play as Jinx or Varus, the only information they get is the champion, no scores or runes or masteries or anything.
Lets say after Bob joins he afks for 5 minutes, he would get the same leaverbuster or maybe even a more harsh leaverbuster penalty because he wouldnt have to wait for the full game to finish after he leaves ( maybe? )
This is sort of what I was thinking, I'm not really sure what kind of incentive there would be to do this which is one of my main concers, maybe a quicker game or maybe have some sort of reward system for frequent replacements ( sort of like the old referral system ) after 100 full replacement games a special skin, or mystery champion / skin, after 500 a forum icon or loading screen boarder, things like this.