I like the game, it's great for worldbuilding and the imagination. However, I do find that the gameplay sort of slows down and the work of creating more nations and expanding becomes a bit tedious.
A couple ideas that could help with this:
Should allow for established nations to automatically expand and take their own actions over time so it doesn't feel like most parts of the map are stagnant while you are focused elsewhere. I like the idea of being able to 'steer' nations towards something but seeing the rest of the map still change makes it feel like the world is in flux rather than set in stone.
Perhaps one way to achieve this is to allow for players to draw 3 cards on each turn for a nation, select one and then see the outcome play out. Example, when an expand card is selected the borders will naturally expand where there is unclaimed territory, where the neighbouring origin culture or religion is the same. Another option is a 'War/Unrest/Conquest' card that causes the opposite, nations will attack or absorb neighbours territory that is of a different religion or origin culture but with high cost/difficulty.
Lastly, is there any way to add tags to the nations? Would be good to see the labels of nations on the map rather than clicking each one. It helps when trying to name nations that are related or part of a broader 'culture', like during splits.