A few things to consider.

  • As was mentioned in the original post, a good part of the early game is simply getting your provinces set up with roads, stable, and actually looking like a civilized place. Perhaps it would be a good idea to simply have everyone start a little higher up in the tech tree to begin with, with minor cities rather than large towns or worse to start with, as well as the ability to build more than just levy's at the very start. Hell, just being able to actually start with some decent professional troops would be a huge plus for a great many factions.
  • Consider allowing each faction to begin with one elite unit - Agema for Egypt, Sacred Band for Carthage, etc. Just one elite unit that they can either disband or maintain and use as a spearhead for their attacks. Adds a lot to the 'elite' factor if there is only one of its kind for a significant period, plus when you do finally tech up and can retrain it then that unit will probably start with a few extra chevrons.
  • Consider bumping up income or reducing upkeep some. It doesn't seem right that all but three or four factions are going massively in debt after turn one. Pontus most certainly fielded a full army with elite troops, supporting troops, etc. with only a couple provinces on the EB map, as did many other factions.
  • This has little to do for peace time, but I think the British bodyguard unit should be changed. As far as I can tell it basically has no viability outside of throwing the javelins...can't even really engage in melee. Historically, as far as I know the Briton nobles of that period simply rode into battle on chariots and dismounted to fight, and did not ride around with a posse of a few dozen chariots watching while his men throw javelins.
  • Scripted rebellions and all sounds wonderful, it would certainly give me something to do as Rome while I'm waiting for the Second Punic War. Got to suppress the Samnites!