Well, unless they're gonna live of marketing they will need to charge players. What you do is make 2 levels. Those who don't pay. They can still play the game and be able to stock buildings and so on, but payers will have a competitive edge, and if they implement some really good political systems (guilds can be an example of a type of "political system"), then leader roles requires you to pay premium account. However when you pay premium aco****, you get the full game, and developers can focus on actually improving the gameplay. Cosmetics might not be tempting enough, and this model is much better than paying for upgrades, or in game currency which debalances the game, and if there's no roof on how much you can spend, those who pay the most wins. A fair monthly pay is a better idea.
This is my opnion though, and it's what I think is most beneficial for gameplay. If they launch several worlds, there could also be a world where only payers can play. Inactivity is usually a huge problem in these games and a premium account only world would very likely drastically reduce inactivity, aswell as being completely fair.