This idea would be a little more indirect than policies and technology. What if you could guide your culture for autonomous, compounding buffs that can be modified with various different interactions? For example, certain interactions could boost manpower growth, research, and economic growth, while certain interactions would decrease this.

It wouldn't be as simple as hitting button to do X, but you would instead begin designing campaigns to introduce new customs which should hopefully lead to intended results. These would not be customizable to keep the game's simplicity intact, but each could have their own unintended consequences. For example, you could introduce the custom of not throwing trash out of your window so the government has to pay to clean it up, (serbia) boosting decreasing government spending. However, since they are Serbian, they will call you a fake Serbian, hurting your political points. These effects could be increased or reduced by the tactic you choose to execute and spread the new idea.

This could help add additional flavor to a nation and boost its potential depending on how well you execute it, but it probably isn't worth adding to the game because of its limited effects on anything meaningful and it mostly being an afterthought. Also, the abbreviation for cultural points wouldn't be so uh.. good

Edit: I forgot to mention it would over complicate the game 🗿

Im just gonna leave it as a concept, play with it how you will