And for PT its even less.
Acclamator Class Assault Ship
and um...Naboo Starfighter?
(I would consider the Jedi Starfighter to be a hero unit, seeing as the Jedi would have force powers that could turn the tide of battle easily).
Republic Dropship (you see them landing the walkers on Geonosis).
The 6 legged walkers from AOTC (I don't recall their name).
Droid Star Fighter
Trade Federation Battleship
Battledroid on STAP?
Super Battle Droids
The small and large spider droids
Granted, I don't know what we will see in Revenge of the Sith but I don't forsee it adding much to that list. Meaning that even if the game was PT based, they would have to design their own units or draw upon EU material to fill out the selection a bit.