Oh totally, it was a bit jarring to me as well. There should, in my opinion, be a whole map dedicated to a swamp, to let the players take in the setting and the mood of that place. Where the farther you go in, the more the feeling of dread sets in. But again - I think that they made it as it is, to crowd the map a bit more and to not let the players get bored.
Whatever happened to beautiful vistas like they were in NWN2? NWN2 is the perfect example that you don't need to smash in a secret around every corner to get the players invested. Appreciating a beautiful scenery (and an 'evil' swamp can still count as visually beautiful mind you) should be it's own reward.
