Problem with people feeling unsatisfied with the ending is that the game didn't make you care about Dyrwood and Waidwen's Legacy. Honestly this felt like a problem in the game in general. I didn't come to care about Dyrwood or the Legacy. I don't care about any of my companions, and I certainly really didn't care about going mad because I am Awakened. So the game felt like it had no purpose. You are just doing stuff because the Journal tells you to do it. The different gods didn't really matter that much, and the different endings didn't really matter all that much. Usually in RPGs, it's really hard for the player to care about something besides themselves. To do that it usually takes a few games to set that tone (e.g., Mass Effect). The problem with PoE, at least for me, is that I didn't really feel personally invested in this whole ordeal. You were told about what would happen to you at the end of Act 1 with Maerwald, but that's it. With just this one instance it doesn't really instill this in the player's mind. As a result, finding Thaos wasn't really a personal thing. Then they kept trying to make you feel curious about your previous life starting in Act 2. The problem, is that the previous life as an Inquisitor isn't really that interesting. They also didn't explain much of it even until the end... so... the game's ending felt anti-climatic and hollow. It doesn't help that the companions were all pretty boring too.