Before i start explaining, i’d like to apologize if something similar has already been suggested/discussed → my topic search was not that thorough, but i haven’t really found much about that.
As we have discussed frequently, the community is divided on whether we need more civs (e.g. some single player players and history enthusiasts) or whether we already have too many civs (e.g. some pro players and some ranked matches & meta enthusiasts).
More civs are generally a great idea to keep the game supported and offer new content for players, whereas it creates the game more complex and leaves more and more civs not being picked in pro matches/tournaments, because different civs have better offers. I understand both points of view and I also agree that some civs really need a bit of rebalance (especially the two new civs and some unique technologies - more specifically those with 1 time only usage) to be more viable/entertaining to play.
There is, however, a solution to consolidate both parties, and that is:
In matchmaking, you would be able to choose civilizations to be banned (either with some proper cap or infinite number of them) and to choose civilizations that cannot be banned - e.g. if one player chooses 10 civs to be banned and the other player doesn’t choose anything as banned, they would match together and random selection as well as civ picks would not allow these civs to be picked. On the other hand, if player A bans 10 civs and player B has 1 of those civs as “ALWAYS ALLOWED”, they would not match together even if the other 9 civs would be banned by player B as well. Of course, if player A bans 10 civs and player B bans 10 other civs, with neither one of them choosing “always allowed” civs, the matchmaking would ban all those 20 civs. This would, on the other hand, prolong matchmaking the more civs are banned/always allowed.
In addition to civ pick, random selection, total random selection and mirror selection, there would be an additional “random from selected” selection that would allow players to choose civs to be randomly selected for matchmaking, so if someone hates playing cumans, burgundians and sicilians, yet they still want to be surprised by matchmaking nonetheless, they would be able to get any other civ by this random option (provided that the civ is not banned as in the point above)
These 2 additions would therefore let multiplayer players ignore new/redundant civs, whereas the rest of the playerbase could receive more civilizations (my personal favourites like Bohemians, Poles, Dutch, Wlachs, Zimbabweans etc…) through DLCs and enjoy their time!