Game Player substitution

I feel like this is a necessary feature due to the amount of disconnectors and afkers. So if they disconnect for more than 3 minutes they will be kicked out of the game and will not be allowed back in. Meanwhile, there will be a special queue for players who are looking to be a sub for a game. Even though that number would be very minimal. It would still help sometimes with teams who suffer a dc or an afk. Please consider this idea because it would benefit the league of legends community! :)