I guess if there is some "real" Anasurimbor that we are waiting for, and its neither Moenghus or Kellhus because they are not, by some miracle, related to Celmomas, than its possible that the prophesy has not been fulfilled, that there is not yet a Harbinger... Still seems extremely convoluted and unlikely.
Actually, I would like to have another Tolkien moment here, but in Bakker-esque cruel way:
1) Someone from these human kennels of the Arc, which were once filled only by noble Anasurimbor captives or, to make things even worse, only by
children of that specific Anasurimbor hero-prince
2) Mekeretrig who elrondly presents him a repaired Heron spear.
3) A strong desire to restore his ancient dynasty in the north.
4) A mission to save all ensouled beings from damnation.
So, to say it briefly. I want the Inversed Aragorn. :3
Someone with unnatural lifespan and skills.
Someone to dwarf "Boromir"-Kellhus.
Someone to fill that gap left after Cnaiur.
Badass. Consult. General.