I can give you a good ratio of what our daughter is doing right now at age 9, per week. 
When not at school, her at-home-time is about 10 to 15% on @synthesischool . That’s about 2 one-hour sessions per week, and whenever she feels like using the Tutor AI (she’ll ask herself to do it at least a few times a week.)

The rest of the time she is drawing artwork (she LOVES art). Talking to a friend on FaceTime while playing video games. Spending time with us. Watching tutorial how-to draw art videos, and a little time watching silly gameplay videos. (We monitor her time and content.)

We think we finally have her doing enough at home (she’s always needed a lot of input). Good ratio of @synthesischool , art, social, and family time. We think this a good ratio for our daughter. And she NEVER seems stressed at all, more excited all the time…..we get exhausted from her lol. But we know what we’re doing is right.

I think you are right, nurturing creativity is better instead of ramming the grind down there throats. They develop better mentally, socially, at a better rate.