I'm in the planning phase of a possible mod to diversify the Roman emergent states and I wanted to get an idea of the cultural individuality of the Roman provinces and what these differences might mean for the roster of a Roman break-off state so that they have more than legionaries to build their rosters on.
So the current focus of research right now is Hispania, but I may use this thread later for other regions as well.
So how prominent would the Iberian tribes be at this point? Using the Cantabri as a starting point, I was able to gather that particular people was able to keep its culture preserved alongside its mythological beliefs until final conquest by the Visigoths. I also know that the folks that made the Brytenwalda mod for Mount and Blade: Warband and the Viking Conquest DLC also feature Cantabrians to a small extent. The Basque seem to be similar in preservation of their culture through the Empire, and they still are rather distinct from the rest of the Spaniards even today.
Particularly, I want to find things in reference to the already-present Iberian cultures and the attitude of Hispano-Romans. The Visigoths, Vandals, Suebi, and others are going to make a strong appearance later, but since their arrival is not guaranteed in every campaign, having those units isn't really realistic. And Romans get their own unique Foederati system already where they can recruit from travelling hordes.