Be sure to lock that user at TL0.
That’s the fly in the self-moderation concept, a few people, possibly just one, can make the system essentially unworkable. Another service (DuoLingo) would hide posts if 5 people flagged them, there were several people suspected of having multiple accounts (from different IP addresses) and they would flag posts from certain users or on certain issues within a few minutes of when they were posted. (That’s a major reason why I stopped using that service.)
Requiring membership in specific groups for those trusted enough to flag posts would be one way around that, with the default being ‘trust level 1’, but a separate by-invitation-only group could be used to control who has that ability.