i've made a map of every civ i think is "necessary" imo to have a roster of civilizations that feels complete for me
bear in mind this is what i think, i've considered historical relevance, cultural diversity and gameplay perspectives:
it's a roster of 59 civs (LOL they are a lot i know, you could remove some of them but for me then doesn't feel complete if i do that)
i've considered also the eurocentrism problem so most of the new civs i placed aren't in europe
the result is that i have put:
7 civs in north america
5 in south america
10 in africa
18 in europe
17 in asia
2 in oceania
of course it's still incredibly eurocentric but at least asia an africa are more fleshed out continents in the roster.
in north america i've put:
america(obv.), canada (because i like the idea of more tundra based civs, also requested, also could give a french vibe to NA), aztec(a given), maya(another obvious), iroquois(because it has been one of the most influential native americans, truly worthy of civilization), cree(canadian NA), sioux (for variety reason, it's a very recognisable tribe, with a famous leader represents perfectly the great plains tribes imo, (people are going to kill me but never mind )).
in south america i've put:
brazil, inca, mapuche, argentina (the ideal choice to represent spanish postcolonial civs, also great choice for a female leader and the main modern competitor of brazil in the continent), colombia ( bolivar it's too significant to be left out, kind of like alexander but for south america)
for the americas i've mixed the roster having equal colonial civs and native american, but still giving the NA the most representation, i wanted to do this because of the unfortunate reality that the americas now have consolidated colonial nations with an interesting history that would be a shame to leave out since it's a big part of the history of the continents.
in africa i've put:
egypt, nubia, kongo, zulu, mali (to represent the niger river empires, the most famous and important), ethiopia (a cultural and religious powerhouse for millennia), morocco (i believe it's the perfect option to represent the berber culture of the desert that connected mali to europe), carthage (important trade empire), swahili (i like the idea to have an african naval powerhouse that focuses in sea trade, also important key of the indian ocean trade), benin (nigeria it's an emerging power in africa that deserves some representation, benin empire is the most iconic imo from the region, also an interesting defensive civ like georgia).
in asia i've put:
china, india, mongolia, korea, japan, khmer, persia, sumeria, indonesia, scythia, georgia, arabia, ottomans, assyria( i'd like to se an ancient warmonger from mesopotamia), babylon( could be interesting to have not just another scientific civ, but a civ that relies heavily on its capital), vietnam (unique culture, interesting mechanics that could be made, also highly requested), siam (i believe that should be a given since with ethiopia they are the "survivours of colonialism", also could be interesting to have a cultural SEA civ, with a jungle bonus and most importantly more elephants UU).
in oceania i've put:
australia, maori(to represent polynesian culture).
in europe i've put:
england, scotland, france, germany, netherlands, spain, portugal, poland, russia, greece, macedon, byzantium, rome, norway, hungary, sweden, austria (major player of european politics in history, interesting mechanics that could be implemented, also i like the idea of a cultural, mountain, diplomatic civ) italy (cradle of the renaissance, major player in europe, also nice economic cultural combination but not militarily powerful, interesting to play as, imo).
of course i'll say again this is what i see as a fully complete roster, could have some addition here and there but i see them as a bit superfluous.