As an Oregonian who lives 3 hours from Bandon, I say this with hope in my heart:
Mike Davis is really high on Bandon and Mike Keiser, and has been from the beginning. . He's already had multiple championships there and just gave Bandon the US Amateur. Don't tell me the Amateur isn't at least a little bit of a dress rehearsal for a slightly larger tournament.
I think that a Mike Davis setup on Trails would be the best host of an Open, I think that Old Mac could also host an Open, but I think the likely winner would be a tricked out Bandon Dunes.
There is enough space on the resort to accommodate all the on-site infrastructure you would need. You might end up closing Trails for the duration of the tournament to make more room as well.
As for the surrounding areas, yes it would be tight, but I think between Bandon, and the North Bend/Coos Bay area, you could do it.
I'll see you at the 2020 Amateur! (*crosses fingers for 2029 US Open at Bandon Dunes*)