The Eastern Desolation as proposed by Grievous in mentioned thread may be fitting for part of that area, but a sense of logic and realism tells me Núrn should have been accessible from Khand and the Rhúdel via a less dangerous route. When pondering this thread, on additions in the east of Mordor, I felt there should be some area in the east where easterlings and variags would have passed more safely.
