My personal biggest disappointment is the repeating point of interest. Yesterday I was on two planets and both had, even on the same planet itself, three times the same mine shaft, twice the same outpost, twice the same hole in the ground, with even mobs and ore placed on the same spots.
Seriously, this should never happen under any circumstances. It was the first time in the game I kind of felt the negative grow. While I still enjoy the rest.
That said, it's also true that the game is average in many aspects, which is enough to be enjoyable for me but not others.