Toxic Queue
(I'm sure this might have been an idea since the beginning of League but I don't feel like browsing forums all day to find it, feel free to link it on here if you know where it is)
Since Rito only bans 0.02% of toxic players even though people probably report at least 30% of the community, what if they just separated the "toxic" (reported at least once in over X% games whether system banned them or not) from the non-toxic players (never reported or reported fewer than X% games played).
So if they set X to 15 then getting reported every 1/10 games you'd be fine but getting reported 2 games out of 10 you should be unable to join any ranked games and only be allowed to play normal 5v5 games with a pool of players who were also reported over X% of games. As the number of reports goes down per game played you'll be allowed back into ranked and normal non-toxic queue but you'll always have to watch your percentage not going up (kind of like how the teamwork/honor badges work except with a higher % to get moved to toxic queue)
This way instead of getting banned or chat banned and making new accounts (I have toxic friends who have 10+ accounts and just rotate when they get banned because they're so used to it) people will actually try to not be toxic to get their main accounts unbanned (especially after seeing how much money people put into some accounts) and will have to remain not toxic to be moved out of the toxic queue (so even if you were put there by mistake it shouldn't be a problem for you to get out and if it is you know you're the problem)
This way for people who are actually toxic and not planning on changing instead of a time ban just letting them back in to regular games where they proceed to troll some more they'll always have to keep their toxicity to a minimum or their percent will just get higher and move them back to toxic queue.