I remember in the old threads of Civ5, Australia was a very requested civilization around here, so much so that there were many mods of the Australian civilization, Canada was almost as requested as it. I think a lot of complaints with the inclusion of Australia was because it was added too early and when the game was very Eurocentric. If Australia had been included in the NFP or GS, I don't think there would be so many complaints.
I don't know if one Polynesian Civ is enough, I think if we have 50 Civs then we can have two of them. We might have a third if we get close to 60 civs. Maori was an amazing inclusion, and I would love to see Hawaii and Tonga someday.
Zulus might show up eventually, but I don't think they should be a staple. They are popular in the media because they were historical rivals of the British, it helps them. However, I particularly find other African civilizations more interesting.
I think America and Brazil are here to stay, they are big gaming markets anyway. Australia I have my doubts but I wouldn't mind if it became a staple either. I have a feeling we will see Gran Colombia again in Civ7.
Both Australia and Canada are certainly popular, on the context of current world is natural for the average gamer to think on these countries when asked for a list of famous countries, but for a game about 6K years of civilizations
their cultures are far from be unique, these countries are the very young and well educated sons of Britannia, both surpassed in every way by their older and more rebellious brother America.
The use of civilizations (plural) refer to distinct groups of societies characterized by different ways of life, institutions, religion, language, etc. We learn about the civilizations of the Nile, Mesopotamia, India, China, Mesoamerica, Andes, etc. But there is a reason the whole modern Europe/Western is seen as a common civilization born in medieval times from the Christian Greco-Roman tradition and "barbarian" (mostly Germanic) dynasties. In game civs like Canada or Australia are the furthest from provide the feel of a different world history born from early cultures with their own unique gods and language. Note that I am not asking for all Europe/Western civ to be one civ on game (also I am sure Canada and/or Australia would come again in CIV7) but a second or even tird anglo-colonial civ is an annoying trend.
The whole idea of Oceania deserving multiple slots lacks justification beyond the idea that its a continent. For example the whole Oceania is basically the same size as Brazil but the later have five times the population of the former. People ask for an australian Aboriginal
civ when their culture is one of the further from fit the imperial urbanized basic model of the game, ignoring Melanesian
cultures that fit a little better (because they are not from Australia
). Then we have Tupi
cultures from Brazil that would also fit better than australian Aboriginals but rarely are suggested when they could be the actual "Jungle civ" with their Terra Preta and their cities in the Amazon!!!