So I'm of mixed feeling when it seems like the vast majority of friction points here surround less than 5 users.
To me, that's the point where the ignore/block feature becomes useful, rather than designing rules based around a small subset of the user base. I understand it can be hard to not see what someone else wrote, but... to me that's a personal decision, not something for moderator intervention. We have stepped in several times when name-calling or other lines get crossed.
One thing that is exceptionally helpful is if people report things: we get *very* few reports, and I honestly don't catch everything as it happens.
I would like to see a much stronger commitment, generally, to people not bringing baggage into threads. We do know each other, but people do evolve: treating each discussion as new, even if it causes us to re-tread ground that may have already been discussed is, imo, a good practice.