[A_Brandybuck]

We know from the Unfinished Tales, that the region Minhiriath was almost entirely deserted, save a little hunter-folk. In my meaning the region of Minhiriath should lie in the new huge realm of Aragorn. So it is likely, that this people will be integrated in the new realm.
I rather think, that there must be somebody at Tharbad to maintain the Ford or the Bridge, which is natural necessary for the new upcoming traffic between the former divided realms. I don't think, that Aragorn would trust the Dunlendings to do that, so there could be a from the king supported migration to that region. He surely had in mind what the Dunlendings did in Rohan. They infiltrated through the gap and took over Isengard. In his case, I would have the fear, that they will do the same in Tharbad or in any other region. Consequently Aragorn would not try to include the Dunlendings elsewhere.

What about Fornost? Could that be, that some Dúnedain lived there while the late Third Age. I mean Butterbur said, that they go there. But why? There could be some hidden dwellings.