I know KLEI already said that they don't want to add steam/PC achivements because it would create achievements hunters, that would try to obtain them and then brag about them, but still. DST is a great game, with A LOT to do, and it would be amazing to have like a "guide" or list of "to do" to guide you through the game. I've started several worlds with up to 8 friends (thanks to some mods) but after deerclops it got really boring, because we weren't having any trouble surviving and we didn't know what to do next.
I also have a +300 days world in DS, and I stopped playing because it got boring.
What I mean is, KLEI, if you add achievements some people will brag about them, but almost no one will pay attention to them. You will be adding players a lot to do, and a lot of people will start playing it again (I know me and my friends would). Also, DST is mostly a CO-OP game, you will be adding a reason for people to improve and get better instead of just starting lots of worlds that last less than 40 days.
I know that this posts will probably go unnoticed, but still, I just wanted to give my point of view.
In case you read it, thank you
(Sorry for my bad english)