As far as articulating a vision of the possible difference between the forums, I discussed it fairly extensively (I think?)
in this thread.
As far as the topic of this thread, I suggested eliminating the !!! threads mostly because I thought it was unnecessarily complicated to have multiple sets of rules. But, I also suggested reframing the rules about the content of posts, and I've talked about having more of a rule against excessively derailing threads than a rule against personal attacks, per se. I think I said previously that I saw it as a rule requiring that you be on topic, rather than a rule that you be polite.
In my mind, that was intended as a compromise position. If we were eliminating the !!! threads, I was also trying to work towards relaxing (to some extent) enforcement of rules against personal attacks in content threads. In my mind, the compromise was with the existing p7 rules, and with the other mods. I took the rule against personal attacks as somewhat fait accompli and nonnegotiable, and since I was suggesting some other fairly large rule changes, I didn't push too hard on this. In practice, I haven't pushed for much moderation of personal attacks.
However, it seems that in the process of going from a concept that made sense in my mind, to my communication of that concept, to the actual implementation thereof, something has gotten lost. I think there are a couple of reasons for that, but part of it is that we three as mods are still trying to work out a little bit how all this is going to work, and we don't all agree on everything. So there's been a negotiation. And I'm sure a big part of the problem is that I was trying to be too nuanced by way of compromise.
Looking at the poll results in this thread, though, I'd suggest that I'd be perfectly comfortable with this sort of solution, if it's really what the overwhelming majority of P7 posters want:
1) Changing the rules to explicitly allow personal attacks, with the caveats that
1a) this is limited by the site-wide rules against posts that are "unlawful, harmful, threatening, abusive, harassing, tortuous, defamatory, vulgar, obscene, libelous, invasive of another's privacy, hateful, or racially, ethnically or otherwise objectionable".
1b) there should still be some enforcement of rules meant to keep threads functioning and reasonably on topic, accepting of course that the topic of threads can be flexible. But I'm not that keen on seeing interesting threads turn into slap-fights on a completely unrelated subject by just two posters, where that makes the thread unusable for everyone else.
2) As a way of mitigating the problem of (1b), re-opening the bad posters thread, as your general catch-all for content-less sniping at each other.
I don't know if this solution is generally acceptable to chez and whosnext, or to 2+2, and I also personally think it will make the forum worse in several ways, and limit the possibilities of it growing. But I also don't think it should be up to me to dictate what the forum is or should be over the objections of a large majority of people who actually post here.