Yes, I feel like we've been using the phrase "national sentiment" in different ways. Probably my fault, since the phrase isn't exactly what I meant. Yes, I'm meaning the collective will of those with power, whether that be despots, wealthy Victorian capitalists, the voting public, Friend Computer, or even (especially in the case of civics changes) a bunch of revolutionaries overthrowing the government. This is why you never lose control of your civilisation, even if you have a revolution or are running a system where power should logically keep changing hands: you're always "playing" as whoever happens to have control over that decision. At worst, you get factions, groups who aren't happy with what you're doing. Which causes unhappy citizens who refuse to work, or completely disrupted cities, or (for people who use Revolution) the country splitting in two or having a civil war.
Of course, that's how things work in vanilla. Doesn't have to be the case in C2C, I suppose. But I suspect that if you do announce that private individuals with power are outside the player's control, and implement that consistently, you'll find the player has rather fewer choices to make in the early eras. You will also be at serious risk, in modern eras, of a problem that Victoria 2 has. In Victoria 2, you have a choice of communist style planned economies where you choose what to build and pay for it from your treasury, or free market ones where you leave it to the AI to build and fund things. But players are much better at making build choices than the AI, meaning that communism is way stronger in player hands than the free market.
For these reasons, I would be very cautious about any mechanic which has the player "collaborate" with an AI to develop the country. Unless that AI is actively working against your objectives.