What other cultures do you think would be added after ''Lords of the West''?

Here are my speculations. Would mention they are also heavily requested by the fandom.

1.Thais, as in the country Thailand to complete the South East Asia civilizations.

2.Something from southern India, since the ingame Indians are mostly based on the northern part.

3.Take and use other Slavic or eastern European tribes alongside Kievan Russia.

4.Sub Saharan cultures to diversify the African roster besides Ethiopia and Mali.