You can also do a greek version of the Pahlavan HA army... 9 units Baktrioi Hippotoxotai and 1 unit Hellenikoi Kataphraktoi. You could have 2-3 stacks of them to be their Hunter Killer armies.

Baktrians were the most "nomad" influenced of all of the Hellenic factions. The armies they fielded at Arreios river were solely cavalry. That is not to say that they didn't have infantry or that they couldn't or wouldn't use it. I think they just picked the best of both worlds.