The story does get more interesting later on. At the start of act 1 you get occasional references to Damian, but not a lot of detail. Towards the end of the act, in the citadel, there are people around to talk to and interact with, and a bit more background.
Act 2 is predominantly outside, with an imp village near the start. There you will start learning more about the history of Nemesis and what happened there after Damian's arrival. Act 3 (also outside, with a variety of environments) has more details on the humans on Nemesis, and their war with the Raanaar locals (some of which did escape the act 1 citadel and are still around), and goes into greater depth about the history after Damian stole something. As far as storyline, act 4 concentrates more on the history right after Damian got there, up until he stole something.
Acts 2 and 3 are also much more open, with more to explore and a greater number and variety of quests (though act 1 does open up a bit towards the end).
