I was extremely pleasantly surprised by the additions made to NPC dialogue in the most recent experimental. Although there have not been many changes, the changes that have been added are extremely useful.
I agree with your image of NPCs from past versions, but in the current experimental it is now possible to RP them as much more sane, non-kleptomaniac individuals. While there isn’t a lot of depth to them right now, it is now possible to imagine them at least behaving in a semi-reasonable way. And now they sleep, which is interesting.
The most important additions:
Command to stop a following NPC from picking up ANY items
Command to stop a following NPC from bashing any obstacles (including vehicles)
Command to give them an item outside of the trade menu (they can hold onto your junk, and you can equip them with makeshift weapons)
Command to reorder their armor
Command to examine their wounds
Command to use an item on them (like a first aid kit)