The scope was amazing, the contrast between where you start and how it ends, the hints of disaster and questioning of your own identity. I found that it brought out the superstitious in me - I never knew why it was important to keep the fire lit and the room warm, but I made sure that it was. I didn't know what charms did, but I tended to take one with me when I went exploring.
The only slight disappointment I had with it was that I was expecting it to be much more story driven, but while there were hints of a story that emerged, I would have liked more.
Did you take builder with you when you left? Were you really part of the alien menace that strip mined the planet? Do you feel different now after having bootstrapped civilization amongst these people? Where did builder learn so much? Did anyone ever catch those creatures in the store room? Will the planet recover? What will you do next?