Txurce
Deity
Still, I don't feel how my society evolves in Civ5 because social policies are a pretty abstract concept. I prefer tradeoffs, even with penalties. A society is not a RPG character. Think about the last 200 years in e.g. an East Germany city: Monarchy => Republic => Fascism => Communism => Democracy. I can't see that in Civ5! "Knowing" Republic and "knowing" Fascism, without Anarchies or losing any bonuses, is not the same.
If you have ever played Europa Universalis 3, nations have a government type that affects things similar to CIV governments. They also have National Ideas, which are like policies. They get to choose these at certain tech levels, and they represent cultural values that remain with the country as you progress and change government types.
The CiV policies are more like the National Ideas. I do not think that the branches should be mutually exclusive at all, but I also don't want to give refunds upon switches. Neither is appealing.
I agree with GamerKG's solution to NPcomplete's wishes: a government modmod.
Would you find it too prohibitive if Cultural Victories required a certain number of great artists to spawn as one of the requirements?
What I like about this idea, given the current state of VEM, is that it could require the generation of Great Artists, even after their optimal landmark creation period is past.