I actually have an idea for the punishment system
Before the permaban, there will be an additional punishment becides the chat restriction and 14 days ban. It will be either before or after the 2 weeks ban. For 10 games, the player would be put in queues together with other punished players.
Maybe players would be reformed when they actually meet this toxic people for themselves. "Oh, is THIS how I behaved?" Also, as they are in games that are only for toxic players that are punished, us other players would not have to be a part of this.
Note that this would NOT be instead of the permaban. This would simply be another step to try to reform players. If they keep behaving poorly after this, the later punishments will of course apply.