I don't know how much they can do. I don't want to speak for the mods, but most of the problems on this site come from upvotes and downvotes. I guess some cheap things you can do are increase the karma threshold required to downvote and apply a smoothing function to upvotes (like quadratic voting for vote scores, aka n votes on a comment bumps the score up by sqrt(n).)
But ultimately a site moderated by up and downvotes that wants to keep a relatively light hand on moderation is going to end up like what HN is today. Changing the voting structure on the site or the moderation POV on the site would be a radical change and could change the entire site's culture drastically.
But ultimately a site moderated by up and downvotes that wants to keep a relatively light hand on moderation is going to end up like what HN is today. Changing the voting structure on the site or the moderation POV on the site would be a radical change and could change the entire site's culture drastically.