The biggest change I want next season
Is how LP works.
I think a vast majority of the toxic behavior comes from the feeling of getting screwed over by the ranking system.
The fact that you are ranked individually by a team performance of strangers is the problem. For those of you that dont know, the ranking system is based on the system used for competitive chess, which works great when its 1v1 matches but not when its 5v5.
LP should scale based on individual performance per game. If you lose but do great, you should less LP. If you win and you hard carry the game, you should get more LP.
That way when you have an amazing hard fought battle for 50 minutes and you squeeze out an amazing play to win the game, you dont feel like its all completely erased in 5 minutes by a troll feeder immediately the next game.
Just my thoughts.