So Act 3 has very high highs and very low lows...
First: Dialogue
For a game that thrives on your choices and the reactions NPC's and especially your companions have to your choices, I was really disappointed at the lack of companion responses. There is just so little they ever say through this act versus the abundance in Act 1 & 2.
Second: The finality of companion quests
I loved Astarion's mission. The voice actor really brought out the big guns with that one. But then....nothing. There was some dialogue but then Astarion didn't have anything else to say. I romanced him so I was expecting a lot more in terms of him explaining how he felt or some new insights on missions etc. It just didn't feel right that everything felt done and over with at that point. I mean, he's still important to the story, right? Doesn't he have anything else to say? That goes double for Shadowheart, Wyll, Karlach etc.
Third: The Ending
I'm not sure I need to go into too much detail since Larian already knows that their ending is rushed, unpolished, and unsatisfying but I couldn't not just express how annoying it was to do all of this and never get any moments with my companions to end it all. No special romance moments, callous reactions to Astarion, Karlach, and the whole bunch. No consequences for having ingested TONS of tadpoles...I mean...it wasn't what was needed.
Overall, I'm still replaying the crap out of it. But had I known all of this, I would have braced myself for an overall mediocre experience instead of continuing to get the quality I was used to.