Perma banned worked for me
I figured for once, I wanted to give you guys a story about the permanent ban actually changing my behavior in LOL.
When you guys handed me my permanent ban I was a little shocked, I knew I was a huge dick when people refused to surrender but the many warnings(and bans) didn't do anything for me. For some idiotic reason it took losing all my skins,progress, account, and friends list to change the way I approach every game.
I just got me new account up to level 30 with no bans or reports. Sadly, it just took muting everyone on the team when one or two team mates would refuse to surrender even though we're getting smoked 35-2.
My behavior has definitely improved since losing my account, and for everyone else, try not to let it get to that point. They gave me a giant 30 day ban before I received the final one, so I think the 30 day is essentially the 'final warning'