Rather than a ban or a chat restriction can their be a new harsher "Ranked restriction" ban?
We've all had "those" players in our ranked games. I'm talking about the players that give up when the game is even and when the game gets tough. There are many players who play ranked "tilted" and bring their negative attitude and behaviors into the next game ruining another match. I just played a game where a bard during the last 20 minutes of our game give up and intentionally feed. And telling our team that we should have been aborted. When the morgana and amumu started taking the base towers he just stood there because he wanted the game to end. Luckily we came up in time to stop them. Of course, people on my team say to report bard in all chat so he says "ill give you a reason to report me" and starts running it down mid lane while we are taking baron we get the baron and fight the enemy at our baron and we kill 3 and leave 2 at very low hp and if bard was there we would have won.
If done by the ban team this type of ban could span a couple days or weeks depending on the offender. Additionally, the raked system could issue like a 30 minute soft ban if a player goes on like a 15 game lose streak because they are probably titled and are causing these loses to happen.
Ranked restriction is absolutely a needed ban type. People like this shouldn't play ranked.