There is one aspect of the buildings I don't like at the moment - burial practices. Currently you can choose Sky Burial with Zoroastrism or you can have the lot. I tend to go for the Zoro option because it removes a lot of buildings from the potential build list.
In general historically peoples tended to have the same burial practices across a nation. These changed over time as the rich tried out something new and it filtered down to the poor or a change in religion or philosophy dictated.
I am suggesting that we could add a bit of depth by adding Burial Practice as something that you choose and that it limits what you can build. I have thought on how to implement it and I think the Civic method is the best even though the burial practices are not intended to be better than each other. There would be no anarchy period for changing burial practices.
The burial practices can be split along the four element line of earth, fire, air/sky and water. There can even be some cross over.
Earth can be further split
- Sacred Cave - bodies are placed in a cave. Later the bones are separated into types that are stored elsewhere in the cave.
- Graves or Crypts
- Necropolis or Catacombs
Sky - I can only think of two here, the Zoroastrism Tower of Silence and the North American Native practice with a platform of wood.
Fire most crossover with others as cremated remains may be buried, scattered on the wind or waves for example. Allows the Funeral Pyre set of buildings.
Water eg boat burial on a river or at sea. Often used with fire.
The South American practice of mummification in cliff caves probably fits into the Sky category.
To these basics are added variations for "grave goods" and mummification.
Such a choice should be made at the nation level not the city level with the old methods going out of use when the new is introduced.