It ended up not being quite as bad after dismissing my earlier hit percentage concerns. That said… it was still a chore to finish, to the point I skipped most of the Act 3 sidequests in the hopes of finally reaching the end.
Compared to the first Act, both the second and third are a bit lacking in stability department (which considering the odd development schedule isn’t much of a surprise). The second in particular kind of falls apart if you don’t do things the ‘correct’ way. Fight the harpers instead of showing them the artifact? A whole bunch of broken reactions/quests is your reward. That aside the area itself is kind of dull with nothing much to recommended exploration, pretty empty as well with only a handful of setpiece battles (though it is nice to have conversational methods of defeating enemies).
The third act also has an issues with sequence breaks. In this case, if you happen to kill Gortash as soon as possible, the Foundry and Iron Throne locations will spontaneously clear themselves. The Umberlee sidequest and Iron Throne also become impossible to clear if you don’t do them before the Foundry. So you’re locked into a very specific sequence of events if you want to avoid having unfinishable quests in your journal. The rest of pre-endgame Act 3 is pretty solid though without anything to complain about. Lots of areas to explore and sidequests to find.
Which brings us to said endgame sequence: It’s real bad.
Why oh why do I suddenly have to run through unending waves of trash mobs? And then fight a bunch of supersoldiers accompanied by a random dragon? And then fight the actual brain itself? It’s a massive, massive slog. Thankfully I had a bunch of Misty Step scrolls saved up so it was clearable first try… but seriously, what an incredibly unpleasant finale.