I thought i'd put out a discussion on the general feedback so far as this is a BETA and in addition gauge the community's feeling on new additions:

More small/micro factions such as Palmyra, Brigantes and an Irish faction.

Emergent factions: Goths around mid game and possibly Sassanids as a rebelling settlement.

Expanding the Capital system to all factions.

I'd also love to hear any suggestions people feel would be in keeping with the mod!