@IronLeonem, but then you create a kind of paused time for the new born where you do what you say. The question is how so? because actually the stats are generated during the “conception”… To me it should be simple, the young hearthling is sent as you say in different structures until adult age (15 years old let’s say) and the result is he get his definitive stats at this moment.
SO tho get it right, we need to introduce genetic within the generation of the new citizen. On one hand part of the stats of his parents could be used as seed for new stats and on the other hand we can imagine that skin and hair color could also depend on the parents genome.
Henry is black skinned with blond hair, he got mind 4, body 5, spirit, 2.
Annabel is a blond white girl with mind 6, body 3, spirit 2.
The baby could be (roll1: 1/2) -> black or white and (roll2: 1/1) -> with blond hair
His stats could be (6+4/5) -> mind 2, (5+3/5) -> body 1.6 = 2, (2+2/5) -> spirit 0.8 =1 (all rounded to next full number)
Now for learning we add a bonus malus depending of the results, 1 got a malus (-0.3), 2 got nothing and 3 got a bonus (+0.3) to learning.
So during 15 years he can improve his stats but because of the malus on spirit, he won’t be able to max it naturally (we can then imagine some way to pass through the “natural” laws with special tasks or something).
So now let’s say you can gain 9 points of stats during 15 years (0.6 per year), you have the choice to modulate the experience of the child by sending him in some specific structures.
Here you may decide to max his spirit and normally you could do so, he is 1, you need 5 and you have 9 BUT here comes the spirit malus. 8 years in the church should theoretically add (80.6) = 4.8 = 5 BUT in reality you get (8(0.6-0.3) = 2,4 = 3 and a final spirit stat of 3+1 = 4.
So if you want to max the spirit by studies, you need 14 years (14*(0.6-0.3) = 4.2 = 5 to get a final spirit stat of 5+1 = 6.
In such case the final stats of the new hearthling would be mind 3 (the last year 2+0.6 = 2.6 = 3), body 2, spirit 6.
So the feature could be fully automated, when the new born arrive, a preceptor panel could open and present his base stats and ask you how you would like to distribute his points of learning (calculated based on the bonus/malus he get). You could do your choices then press ok and then the child during 15 years would be autonomous, wandering from school to gym to church to home, playing with other children or domestic animals during free time etc…
AND at 15 years old, a special event would happen to make him an adult, kind of banquet or something in his honor.