my rookie I drafted this year was 19 year and MVP.
He had 43 skill points, so not a great prospect in my view, but due that I didn't have money to buy a better trainee, I decided to train him. Also because his TPE was between 20k and 50k.
Now his TPE is 250k to 400k. While he has had 8 pops on 6 skills.
So even from a financial point of view, it was wise to train him.
So I believe that 19 years old with good potential have more value than credited for!
Only in the dark, we succeed!