It's more like Baldur's Gate --> Baldur's Gate 2. Yes, there are fewer environments, and you revisit them more often (so the scale of the game is smaller), but you're not going to yet another nameless field to find one thing and then leaving to never return. Each of the areas is more detailed, with more things to do within them. The reuse of the cave (note sigular) can be a bit annoying, but I honestly just got over it.

The story alone (just like Baldur's Gate 2) more than makes up for the negatives. The characters push that further, and the combat is very satisfying 98% of the time.

There is also no "DA:O Deep Roads" kind of section which takes up a third of the overall game and is 10x as boring as the rest of the game.