It occurs to me that this sort of thing might be good to explain in the tutorial.
Setting up buildings in the settlement, as well as gathering survivors (and how/where to go about doing that) is one of the things the game doesnt seem to explain very well. Which is odd, since it's darn specific about where exactly to find pretty much anything else. And survivors/buildings are pretty important from continent 2 - onward.
I really dont remember this being explained well, if at all. Certainly, a note about them being easier to locate in caves would be nice; particularly since cave exploration is a good idea at that point anyway, as you can get extra shards from enemies and the frequent boss rooms, as well as start collecting granite and other stuff.
I also dont recall much explanation as to just how all of the professions work.