Money changes everything. In theory volunteer moderators are a good idea. But, I’ve been on some forums that have been run like a dictatorship because the moderators were volunteers and thus didn’t feel beholden to an actual boss. To be clear, this wasn’t some random internet forum, but a forum that postdated the club that it worked for, a club that is over 50 years old. But the President of the club didn’t have much, if any, sway as to how the moderators conducted themselves. It resulted in havoc.
That’s one reason that I think that it needs to be professional in nature and a paid position. That should limit the personal nature of a moderator or a group of moderators actions.
I don’t mean to shoot down your ideas here, but I think that there also needs to be some transparency as to who is making a given comment. So that they can at least attempt to keep track of people that would use the same e-mail address to create a different account to try and get some jabs in. Granted, people will most likely just create fake accounts and the action of the moderator would basically be to stop aggressive or damaging comments from reaching an author.
I don’t know exactly what process would be used to determine who is in need of protection when and why and for how long. But, in some cases it is obvious that an author is being aggressively abused by a swarm of roaches.