I agree with the others here that aren't keen on adding missions. I think the implementation of additional mechanics like barricades and the like will promote more robust gameplay. I can envision entrenching an area with a group of friends and defending it as we continue to explore and gather materials for further expansion. I like notes or clues but missions to me sounds like questing which is not why I love this game. My favorite aspect is that everyone can approach the apocalyptic scenario and survive it in their own way.