Would it be possible to implement a system where when someone afk's or disconnects after a certain amount of time, a player who joins a specific queue would jump in mid game and take their place? have that person replace the AFKer with the same runes/masteries/spells till the end of the game. You could even award that player extra IP for being stuck with a "random" champion for the remainder of a game.

something needs to be done about people griefing/AFKing, and with a matchmaking system already in place it wouldn't seem to be that complicated to implement.

I would queue specifically to fill in those spots, just to try and help with the problem.

Nope, terrible idea.

I like the idea. Sometimes I don't feel like playing a whole game, so the ability to drop into a random game would be pretty nice. People who go AFK should of course still receive full penalty.

It'd have to have a limit. The missin' player would need to have been gone at least 10 full minutes.

I hate afk'ers

It's a good idea in theory, but logistically, I can see it being a nightmare.

Would a player join the queue, hoping for a champion they know how to play?
Would they do a champion select, and get in a separate queue for that champion?
How would the queues differentiate between a person who has simply lagged out for a minute?

I love the idea, but I don't see how it would work.

I actually love the idea, just not sure as to how it will work out.
I see a couple complications in a few different areas.

Like someone had mention before, the person AFK or disconnected would have to be away for like 10min before a sub would be put in.
Problem with this is 10min is a long time for the apposing team to get ahead, but its better then nothing getting a sub at sometime.
Reducing that time to 5min I think would be better for one.

A large problem would be the sub. Getting masteries and a hero you might not be familiar with could be worse for the team then just playing 4v5.

I love the idea, but i can see some harsh consequences, but some great benefits if its implemented.

Maybe they could have some sort of voting system, might not be the greatest thing but still.

At the end of the match you care rate the sub from 1 to 10 on his performance as a sub.

When a sub is about to be summoned in, the team with the AFK can vote the sub in, or wait for the next one kinda thing.

WHat if someone gets a champ they dont know how to play then feeds but he/she didnt really want to.