You're talking about two types of abuse.
- A. Abuse of the systems.
- B. Abuse of the individual.
I can't see Abuse of the system ever being solved, in my personal opinion I think the whole platform is riddled with hustlers from things like cliques only voting for their mates, upvoting groups, games and voting bots designed to reward the developer, sock puppets and a whole raft of practices designed to squeeze as much as possible from the blockchain. I suspect any attempt at managing this problem will be like playing Whack-A-Mole, why? Because there's crypto to be earned and so it's worth the effort to get around any obstacles steemit inc try and put in place.
Abuse of the individual should be easier to achieve although again if someone is determined to make a users life hell they'll just keep making new accounts.
I never was that keen on the old idea of running to Discord with your problems, I do kinda like the idea of some sort of official body you can contact although I'm not sure "Witnesses" are the best choice for this, look what happened last time they didn't like a decision. The problem, of course, is you can't promote something as "Free Speech" or "Uphold the values of Freedom" and then with the next breath argue "So long as it's our view of Freedom."
and as for enforcing some rules: Quis custodiet ipsos custodes?