Appeals Committee. Disputed situations in tournaments.

No, a cheater will never correct themselves unless they are punished. There should be one warning. For example, their avatar could be displayed prominently for a period, and after two years, it could be removed as if they have completed a rehabilitation period. If they are caught again, they should be banned from all official tournaments. And during the two-year rehabilitation period, they should also be banned from tournaments.
I also want to add that everyone should be able to see who they are dealing with, so the avatar should clearly display that this person has a mark.