I remember one time someone said that the Nabateans were going to get a Hetairoi unit. I also recall that someone said the African roster was almost complete. I wonder what's left to do in terms of units since Gallia, Iberia, Asia Minor, The Balkans and the steppe are pretty complete.
Aside from the Germanic/Baltic rosters, some BGs and some elites, I think EB2 has a hefty roster of units indeed and one I can say i'm satified with.