I realized that after trying Civilization V and being disappointed with it, I became a little obsessed over what I would do to make an amazing Civilization VI. I decided to write up my ideas and share them and see what other think. The results have been split up and placed in several posts like the one below.
Culture This could be global, and could be used as a primary mechanism to limit empire over expansion. It makes far more sense for culture to be global than happiness. This global culture could be divided evenly among all cities and then the individual city values could be modified by buildings like libraries that increase city culture by X%. Global culture could then be increased a little for every social policy (like civ5), wonder, or religion you have. Because the land available to cities in recent Civ games has depended on the culture in the city, this would give players a choice between having a small number of cities with a lot of land or a large number of cities with little land, rather than creating a set strategy that most players must follow. You might also have to have financial costs like there were in Civ4 but the costs would not be the primary limiters of growth and would not have to rise at such a shockingly fast rate.
Culture This could be global, and could be used as a primary mechanism to limit empire over expansion. It makes far more sense for culture to be global than happiness. This global culture could be divided evenly among all cities and then the individual city values could be modified by buildings like libraries that increase city culture by X%. Global culture could then be increased a little for every social policy (like civ5), wonder, or religion you have. Because the land available to cities in recent Civ games has depended on the culture in the city, this would give players a choice between having a small number of cities with a lot of land or a large number of cities with little land, rather than creating a set strategy that most players must follow. You might also have to have financial costs like there were in Civ4 but the costs would not be the primary limiters of growth and would not have to rise at such a shockingly fast rate.