In my opinion Latin America needs:
New treasures, and correct existing ones so that they are not guarded by outlaws from the old west.
New outlaws in the bar, tavern, etc. who are of an origin according to the region. Like I said, Old West outlaws don’t fit.
Could there be mercenaries of Latin American origin? It would be interesting. I think these could make sense from age 4 onwards.
Revolutions with more historical precision. I doubt that the South American nations had access to machine guns and armored ships.
New maps (biomes) and natives. Zapotecs in the Amazon, what?
Naval and river trade routes. (also for Anglo-America). I would like, for example, for the map of Spain and the Caribbean to have naval trade routes, and the Amazon River to have a river trade route.
If new civilizations are added, it should be through historical campaigns and battles. Aztecs and Incas need campaigns. The independences could be campaigns that represent civilizations such as Brazil, Greater Colombia and Argentina.
Rework existing natives. A couple of new upgrades/techs, a buff on the upgrades/techs and existing units if necessary, and also some new units at each TP. (I also included Asian natives, and those from America in general). They feel outdated compared to native Africans and Europeans.