Also, my ideas for civs and their unique units. We could make two unique units for each civ, but I don't know enough about each civilization to come up with a second one for each one.
Athens= Some kind of Trireme, the current Phalanx replacing spearmen
Sparta= Spartan Hoplites (stronger phalanx, replacing axemen), current Phalanxes replacing spears
Macedon= Companion Cavalry, Piked Phalanx (The varietas D. mod's greek pikemen come to mind)
Rome= Praetorians, some kind of earlier legionary
Carthage= Numidian Cav, War elephants
Phoenicia= Some kind of Galley, some kind of Trireme
Persia= Immortals, War Elephants
Egypt= War Chariot, no idea
Bablyon= Their current bowmen, the Sumerian vultures
Hittites= Bronze chariots, no idea
Assyria= I don't know enough about them
Celts/Gauls= either woad raiders or some sort of Gallic warrior, or both