The issue with the behaviour system is that it is too black and white.
Disclaimer: I am not currently punished for behaviour. The behaviour system works like this: It has a list of phrases and words that are considered "negative". If a player is reported, the system compares the chat logs of the player to the list of words in the system. If at least 1 of the words the player said is in the list of negative words, the system issues a punishment to said player. This punishment scales extremely rapidly to the point were the 4th punishment is permanent ban. You can only go down a tier if you go 3 months without getting punished again. 3 months is honestly too much for reforming. It should be about 20 games without getting punished again to be considered "reformed". This will keep the players who are constantly toxic punished, but will be more fair to players who frustrated every once in a while.