I Know ya'll have no plans for a Roman Faction (I can understand given the date) but did ya'll consider the Latin Alliance In Italy. at the time made up of many Latin Tribes (Including the Romans). Since around 496 when Rome was forced to join the alliance, it was just six year befroe the battle of Marathon.
Not to mention it could give ya'll another faction in Italy. I know this is a little late to be mentioning and i am sorry, and the decision is yours i have no quarral with that, but i am curious.