Wow, that's kinda interesting. I didn't remember that 1e's Hell was so different. I guess it's been a long time.
Although not official, I'd like to at least mention Chris Pramas (since he wrote officially on it in 2e) take on Hell in Legions of Hell where Bel is Baal and is a unique devil, not a fancy pit fiend (a position I think makes a lot more sense), in place of Levistus we have Leviathan--the gigantic unique devil whale creature--and in place of Malagarde or Glasya either one we have Lilith, which has a Judeo-Christian folklore paternity that is unshakable.
My own preferred version of Hell is a combination of the Fiendish Codex II version and this Legions of Hell set-up. Bel and Baal are alternate spellings of the same idea, and I prefer archdukes be unique devils, so I'd just change my Bel to Baal in appearance and name and otherwise use his stats (if ever needed) as is. FC2 seems to strongly imply that Levistus being put back in charge was a distraction while Asmodeus worked on getting Glasya where she is today and that now he's worried that his usefulness is at an end. This opens the door for Levistus being taken out of the picture and replaced by Leviathan. Glasya and Lilith are similar enough in concept to assume I wouldn't worry about coopting Lilith--I might go so far as to consider it an alternate name for Glasya, although FC2 does mention a Lilith as a second consort of someone in one of the courts of the archdukes. Can't remember where exactly.
That way, I get the best of both worlds, and I can actually make the "official" stance work in my campaign--just advance the timeline and introduce a few minor changes. Legions also posits Baalzubul and Belial as fallen celestials rather than baatezu per se, which I think is a cool idea, but not important at the end of the day. After all, the Pact Primeval myth has all of the devils as fallen celestials if you go back to ur-time. I do like the idea that Baalzebul overcoming his slugform punishment too. The idea of all these archdukes being publicly punished but left in charge of their layers strikes me as a bit bizarre, so I'd either remove the punishments or remove the archdukes depending on how I wanted it to go.
Anyway, sorry--I know the thread is about the official position, not what we do in our own campaigns. I'll shut up now.