I found the first area pretty filled out, but leaving that area had a massive drop in the quantity and quality of quests and combat. The survival elements are tacked on and never take a major role; or at least they didn't when I first played it. I have not followed the game at all since I stopped playing. I know they've patched it.
I thought there were concerns that the reviews were "padded" by the developers, but I could be wrong about that. It would explain why they fell quickly after the first several weeks. Most games make 90% of their money in the first couple months.
Finally, I thought the game was worth the purchase price at the time of release and will play it again someday. I was just bored with the other areas in comparison to the first.