I think the developers should release larger DLCs from time to time. DLC with 2 civs + 3 campaigns is not enough - I prefer to pay more, but get more for it.
I think the creators could create 2-3 larger DLCs (4-5 civs): African, Forgotten Empires 2.0 and Balkans-Caucasus. Between these DLCs there could appear smaller LotW-like and DotD-like DLCs, e.g. Indian DLC (Bengalis, Dravidians + Punjabi), South American DLC (Chimu and Muisca), North American DLC (Mississippians and Tarascans), Icy DLC (Finns and Inuit) and Last European DLC (Bavarians, Venetians and Aragonese).
In this case, I think the developers should now release a large African DLC and then 2 American small DLCs (South American DLC and North American DLC). After adding love for Africa and America, the creators should move on to Asia. Finally, there would be a return to Europe - the Balkans, the Caucasus and the great Western empires. On the occasion of the holidays, it could be done DLC with Inuits and Finns.
If the creators decide that this game will be further developed, I think that they would only then focus on non-European regions - they would have a lot of time to look for non-European inspirations for new DLCs.