Why will they become a neutral faction when they are here?
Amirdrassil should become an Alliance place as Suramar and Highmountain are a Horde place.
I think many of us just want a statement about the state of Kalimdor in Darkshore and Ashenvale for the Night Elves (with Winterspring and Hyjal too) in the lore and in the books but also this:
Blood Elves will get a massive update of their lands in Midnight so Night Elves could get the same thing for Darkshore and Ashenvale with the new assets of Amirdrassil (Zidormi is still here if you want the old version or the ruined version). Of course don’t forget Gnomeregan and the Azuremyst Isle for an update of their assets too.