I'd drop Night Elves and Undead. Forsaken make no real sense. The shamans and druids that the horde is based around make no sense letting the Forsaken ally with them. Same for Night Elves and the Alliance. Between their savagery and watching the humans chop all those trees on Hyjal the make no sense in the alliance.
I'd prefer to see them replaced with High Elves (A) and Ogres (H). That would really flesh out the nostalgia from W2.