Just gonna write off the Ottomans, Portugal, and Inca since I think their inclusion is more or less a guarantee - even though I'd like to see them. Also not gonna touch the Maori/anonymous Berber Civ since if the leaks are real, they're confirmed. Though I'd like to see a Moroccan Civ more, Algeria could be very cool too. My personal wish list would be:
Maya: I think the Maya are a very interesting culture to study, and I really enjoyed their presence in Civ V. Their strong science and religion output gave them a strong early game, and their calendar UA was one of the most unique abilities in the game. I'd love to see them return with a similar design plus a LA that emphasizes wonder/building construction.
Mali: Come on, Mansa Musa would be a great personality to add to Civ VI. One of the richest people to ever live and who single-handedly controlled the price of gold in the Mediterranean? Seems like a shoo-in to me. Plus they're the most significant empire in West African history. The only bigger "gimme" African Civ to add would be Ethiopia, and while I'd like to see them added too, Mali's absence from Civ V due to the Songhai didn't go unnoticed, and I'd like to see the Mansa back.
Iroquois: The Iroquois are arguably the most noteworthy Native American group you could add, and I'd love to see them return in a better representation than what we got for Civ V. Keep the forest-theme, but make it less awful.
Austria: Maybe I'm the only one who wants to see this one, but like I said in the main discussion thread, their importance to the development of Europe is just too big to overlook. They were one of my favorite Civs in Civ V, had a super unique niche, and I'd love to see them again.
Babylon/Assyria: I love my Mesopotamian Civs, and while Sumeria does fill that niche, it doesn't sate my hunger. Since we do have Gilgabro in the game, I doubt we're going to get both of these, and out of the two I'd prefer to have Babylon. Just make it a science Civ, put Hammurabi in as the leader, give him an ability that relates to the Civic system, add whatever buildings/improvements/units you want, I really don't care. Just give me more Mesopotamia.
Southeast Asia rep: Dai Viet/Vietnam or Sukhothai/Thailand, either is fine, I just want more Civs from this region. Thailand probably makes the most sense, since the Khmer kinda cover Vietnam, but either one you could do a lot of neat things with.
Byzantium: There's some argument over whether or not Byzantium could be considered a Roman-alt leader, but since their culture/language/history was distinct from what we consider "Rome," they're a separate Civ in my book (even though they called themselves Romans).
Navajo: To differentiate from the mainly arboreal Native American Civs we've included, let's get one out West. The Sioux/Lakota might play too similar to the Mapuche (fast-hitting horse Civ) and the Shoshone might play too much like the Cree (exploration/expansion Civ), the Navajo seems like a solid inclusion. I'd personally like to see the Pueblo, but given the circumstances that prohibited their inclusion in Civ V, I doubt we'll ever see them. I'm not quite sure what their uniques would be, but nonetheless I'd like to see them. Maybe add an Apache Civ in their place, but either would be good. From what little I know between the two groups, however, the Navajo might make a more distinct Civ.
Cherokee: A Cherokee nation could also be quite good, since they're the largest federally recognized tribe in the US. Their niche of dealing with a colonial government might be covered by the Cree and Poundmaker, but I'm sure there's still something distinct you could do with the civ. John Ross/Koowisguwi is a natural choice for a leader.
Post-colonial South American nation: I just want to see another SA representative besides Brazil. Chile could be an option, but assuming we get the Inca, their location might be problematic. The best representation would probably be Gran Colombia or Argentina. Argentina probably lends itself better to mechanics, but Simon Bolivar practically is begging to be a leader in the game.
Swahili Nation: It hasn't been included in a Civ game yet, which is a damn tragedy (especially since Baba Yetu is in Swahili!). Kilwa, Mozambique, Mogadishu, Zanzibar, I don't really care which one makes it in, just add one.
Beyond those major ones, I'd also like to see Celts/Ireland, Ethiopia, Chinook, Shoshone, Sweden, Hungary, Denmark, Carthage, Hittites, Afghanistan, Italy (Or Genoa, Florence/Tuscany, Naples, Venice), Ashanti, Benin, Muisca, and the Haida. There aren't any Civs that I really don't want to see, as long as they play well.
That said, PLEASE DON'T ADD SOME LEADERS JUST TO BE CONTROVERSIAL/FILL A GENDER DIVERSITY QUOTA. Seriously, if you want to add female leaders, there's plenty of really great options! Theodora, Elizabeth I, Isabella I, Maria Theresa, Catherine the Great, Lady Six Sky/Yohl Ik'nal (though Pacal I might be better representation), Eva Perón, Wu Zetian, the Trung Sisters (two leaders would actually be a really cool change of pace!), Boudicca for the Celts (though I'd prefer an Irish-Celt civ since we have Scotland), Hapshepsut, Caterina Sforza/Margherita for Italy; hell, I'll even take Dido for Carthage. Just please, please, don't do something like make Eleanor of Aquitaine the alt for France; though I like Catherine in the game, I don't want the whole of France to be represented by a leader that has a lot less historical importance compared to Louis XIV, Napoleon, Charlemagne, or Henry IV.
