I like how Act 3 feels like a real town and there’s so much to do in the space, with character moments everywhere. I just don’t like how incomplete it feels— some quests end abruptly, some moments are squandered if you don’t have the right party, some characters wrap up in unsatisfying ways (both from earlier acts and from BG2 but that’s a separate issue), some decisions aren’t acknowledged, bugs cut necessary material, and it can be confusing to navigate the quests sometimes.
On the other hand, Act 3 doesn’t have the theme park effect, and I quite like not knowing where to go sometimes. It gives ambience. I just wish my party had more to say during those moments where I’m wandering the same streets aimlessly.
I like Act 3 more than Act 2 overall, and I like how Act 3 is so different from the first half of the game, but I think it needs some polish and tying up of loose ends, particularly for recurring NPCs, companions, quests, and prior decisions.