So while yes, it's good to remember that DnD's Hell and particularly Avernus is not a stereotypical pit of misery, I don't think Karlach's issues with it - and with going back there - are negated by the fact Tav's going with her and it may be better now. That sure helps, but that pent up years-in-the-making repulsion doesn't just go anywhere. Even if they are given good positions and conditions and stay together, going back at all is gotta sting.
(Not to mention that on behalf of the character narrative that would kind of feel... patronizing, I dunno? Like, 'See, it wasn't that bad here, happy to see that you finished having your little tantrum and returned where you belong'. Not the worst ending, sure, but frustrating nevertheless.)
100% Agreed.
While I can certainly entertain Doomslaying, a front against Zariel/the Hells and fighting through them. I see no way to justify being in Avernus for any purpose other than to find a permanent solution and way out, using the House of Hope as a half-way refuge type deal. It'd require a super satisfying piece of writing to make an expansion on the Avernus ending as good as/better than simply using the tools available during Act 3 of the game (The Gondians) to create a holistic, and well written positive ending for Karlach that completely nullifies the need to, for lack of better words, "return to sender". I don't doubt that Larian is capable of performing either, if not both of those feats, given their positive history.
