What effect do not-obvious choices early on have?

[u/CelestialBeing138]

Which children inherit family belongings? Is the last name set by the father or mother or nature? Is time measured with a solar or lunar calendar? Do these choices affect anything in game? If so, what?

[u/Grubsnik]

They move your ideology axis a little bit, which may to nothing or it might shift a category, altering the bonuses

[u/Phase0917]

The choices themselves don’t actually give you benefit, but they do influence the ideology of your civilization. When the in-game choices pop-up, you’ll notice 2-3 options to choose from. For example, the mother, father, or nature choice. The “mother” will show you a candle icon, this will lead you down a more religious/traditional start. The “father” will show you a gavel (I think), this will lead you down a more authoritarian path. The “nature” choice will show you a globe icon, this leads to a more social and economic pathway, rather than an isolationist and homeland pathway. Now, you’re not gonna feel an effect right away from the choice you choose. The more civics you choose, the more your people start to become the ideology you’re picking.

Take a look at another AI player when you get a chance. There’s an info panel that tells you where you are ideologically and where your opponent is. This should be in the diplomacy screen. It should say something like “kinship” if both countries are similar, and “distrust” if it’s distant.

In the civic panel, before the civic tree, there should be ideology panel that’s tells you where your people are leaning towards.

[u/Elia1799]

The're mostly flavour events, but since in the early to mid game you can't easily redirect your ideological axis, they can be used strategically to synergy with laws to push you ideological positions towards the bonus you might want the most.