Retaliation option for griefers
Something needs to be implemented which allows for active punishment and prevention for griefing. I know riot has been tough in the past with banning anyone they damn well please. Although it doesn't solve the problem of active, more or less real time, community prevention of griefing. When you get into a game where an ally walks into the enemy team/turrets dancing. Then it's made all the worse when you can't even end the game due to them having a friend with them to stop the surrender vote.
Then you know damn well the other team will not surrender, because hell it's a free win. Also we've all seen it where someone is so far ahead they can't possibly lose, so they delay winning the game. Meaning the people on the team getting completely screwed over are trapped in a 40+ minute game where their team can't win and the enemy will not try to.
The funny part is, that i'm not even talking about losing LP or failing a promo because of this. I'm talking about unranked, purely wasting someone's limited time because you feel like being dick and there is nothing they can do about it, because most systems off the top of your head can be abused.
Something needs to be done. Even if that means giving more power to the community. One unique system i thought of was an adaptation of the spectating system and tribunal. Where players can put in a ticket to have their game reviewed by others of the community. Players can watch a random game, that's been reported for a greifing player, and maybe 20 random people spectate the game, vote, and can end the game early in a draw. Obviously there has to be some reason people would do this, and to put it simply IP. I mean voting would be pretty quick and simple, and you could add in a type of daily bonus system so that more people would be willing to put in 5 minutes for an extra 100 IP once a day.