Ive seen The New Karlach ending. Its certainly a massive improvement. Personally Im satisfied with it. Id rather see more effort into The other romances/endings and epilogues. The Laezel one certainly felt a bit lacking at The ending. Both in choice and tone.
Id rather see their efforts in restoring Minthara Romance. Re add Jaheira fling. Fix Gortash cinematics if doing Odin first. Fix Emperor inconsistencies. More reactivity from companions in Act 3 etc etc.
What makes it satisfactory, if I may ask? Maybe I could learn something from your point of view.
Your love and awesome companion HAS to go back to hell as it is. You get to join her there, and we now have a slightly extended version of what that looks like. And you can bring Wyll along. Without the new scene, one could easily imagine her being alone, afraid, desperate, and who knows, she swore to not go back, so she might end IT if she went there alone.
Im sure many would like a way to fix her infernal engine, but with that option not on the table, this is the next best thing imo. Its satisfying because we get more closure. Its also satisfying in the sense, that sometimes life is hell (no pun intended), and theres not much you can do about it. But your friends and loved ones can help you along and make it bearable.
I personally thought it was an amazing arc, if a bit sad.
"They say he who smelt it dealt it." Sooo technically... this burnt corpse is your fault officer."