I actually like that he has this mindset as a child, not a person who has lived to adulthood and gone back in time. He just a gifted kid who got burnout while still young and has been plotting since to avoid a life of overwork.
I didn't even check the summary I saw the cute thumbnail and clicked. It's a good story so far and there are even more cuties than the picture so I'm happy
I'm impressed author, they managed to squeeze in a sports festival special into this plot somehow