There is subtlety in the superb acting of Neil Newbon. Emma Gregory, Andrew Wincott, and many other actors are also superbly acted.
Astarion impresses not only with his lines, but also with his facial expressions, movements, and voice intonations. I really love his romance of the first act, it's really seductive, and somewhat reminiscent of the seduction in the style of a flamboyant pushy young nobleman from 18th - 19th century novels, there's a bit of a modernization when he voices what exactly he meant, but it doesn't spoil it. It's clear that he's not in love, and such an untrusting character with his history can't be in love, you still have to earn his trust, but his scenes evoked real emotion from me, and that's the reason I agreed to turn a blind eye to all the other problems with this game. Lae'zel is shocking and makes me open my mouth in surprise on first playthrough, but that's normal for githyanki culture, it fits into her character. The really jarring part is Halsin, especially at the party. The way he looks at Tav makes me want to take a step back and put my hand on the hilt of the blade. Obviously, he's officially "kind" and isn't supposed to do anything wrong in the story, but on a feeling level, as a woman, that look makes me want to grab a weapon or take a fighting stance, just in case.
I agree about "Mask of the Betrayer" and "The Witcher." It really does show the romances in a richer, deeper, and more aesthetically pleasing way. About the awful dialog phrases, yes, more than that. Some phrases are exceptionally facepalm-inducing, I've never read sloppy fanfics before, but thanks to BG3 I had to embrace this art form as well.