I’ll be a contrarian and throw in my vote for the second game - it’s rushed and flawed and the asset reuse is blatant to the point of being legendary, but the setting and story are the best and most original of these 3 games. Just being a hero of one single city instead of the entire world is surprisingly refreshing.
In general I’d say that 1 has the best combat/tone, 2 has the best setting/story, 3 has the best characters. I’ve heard that 3 can be quite enjoyable if you pretty much only do the main story and companion quests - but I wouldn’t know, I’m one of the poor fools who got stuck in the Hinterlands, and that mistake + the very underwhelming main story sapped my will to continue playing.
Yeah, one of the only games I’ve 100%ed, the achievements are deliberately set up so that you can get most of them organically by the time you get to the true ending. The rarest achievement on Steam has like a 6% obtainment rate, which is a lot.