There's a very simple solution that isn't extreme, and doesn't severely punish the occasional leave.
You cannot join ranked games or normal games unless you have less than 10% leaves of all of your games.
This allows for the occasional leave, and allows you to redeem yourself if for w.e. reason, your grandma dies 50 times.
Well, guise, you forgot, that you could only leave once, then reach back up to 30 to play it again. So no, you can't just get to level 1 through deleveling.
And 24 hours ban in straight off too much, you could solve a every electrical problem in powerplant during that time and then come back, and you even would do it, but they don't allow you.
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