Here are a couple suggestions to refine settlements a bit. One is an adjustment to settler assignment, the other to wall/fence construction.
Assigning settlers can be a great annoyance in any but the smallest settlements. Unless their assigned object is in your Field of View, you cannot tell what they are assigned to. Yes, objects are highlighed, but you cannot see them through any obstructions. I have come up with a simple way to make the assignment process more intuitive, and prevent unwanted reassignments.
When a settler becomes assigned their name changes like Provisioners do. Like Farmer, Scavenger, Guard, and Salesman. Unassigned Settlers could just be named Settler. For Named NPC settlers, perhaps they change outfits. Another way it to have Icon's above a selected settelers head showing their assignment type.
For Wall/fence construction, the Shack foundation is the only object that adapts to sloped terrain. there should be some type of fencing that does the same.