Keep in mind that for some factions we have a *lot* of different ethnicities. For KH for example - we will have in future builds a whole lot of different places your generals can come from - though early on they will be primarily kids of spartans and such.

Seleukids will have a lot too, and ptolemies. Epeiros has a number too. We can get pretty detailed - as long as the whole system works together and is reasonable. The royal families might get influence boosts, to help them keep power and the title of king, but if some other general (maybe who starts out with an influence penalty) rises to power and overcomes those deficiencies, then he could start a new dynasty with his ethnicity or other type of special description.