I started a short game with the Seleucids myself - not going too far into it since I still had my long campaign with the Julii to finish up. You start out with some real handicaps with them. Limited early funds, threats from all sides - Pontus, Armenia, Egypt and Parthia. Parthia is particularly tough because of their extensive cavalry. My hat's off to you 'BHC'. One of the reasons I'm having such success with the Julii is that I get the best of infantry and can produce a lot of cavalry that are not just of the skirmishing type. Parthia came at me in a surprise attack and their army had both skirmishing cavalry and heavy cavalry. If you don't match their numbers on horseback, yuo can get into real trouble. The game hadn't progressed far enough for me to produce similar units. The style of combat you must employ with the Seleucids is much different too. Good luck in your endeavors.
more later . . .