I was thinking - when we get to diamond city, we have the option of telling what's-his-name that we that we've got a caravan coming. Why not, though? Could someone set up a mod which creates a caravan which can go to diamond city, once the player has a big enough group of settlements? Also to goodneighbor, and Vault 81, possibly atom cats? I don't know, in my idea, they'd take goods from the settlements, and return with caps... For me, at least, the ideal mod would be Sim Settlements compatible.