Hello Riot, have you ever thought of a customized block system?

I was thinking at the friendship system. If you enjoyed to play with a summoner you just met, you can add him as a friend and play again together. So why don't do the opposite too? If I play with someone who really made my game miserable I would like a button to "block" him and prevent the game to match me with him again. He's not banned or anything, he can still play with somebody else but I will be sure that I wont meet him again. This way people who deserve to be banned would be naturally isolated, while people who just got angry for 1 game will still have the chance to behave correctly with other players.... what do you think?