I think it could be interesting that some real life objects (like the Venus of Willendorf https://en.wikipedia.org/wiki/Venus_of_Willendorf) could be created in the game (a small percent chance of creation for each object). It could be notify to the player with a picture, a small description and perhaps the musuem name.
I do not know if they should give bonus to player (maybe moral, entertainment or religion boost) or just for fun.
It could be a nice adidtion to the game and maybe people will go see it in real life.
What is your thought on this ?