He is young and short so should train fast. He should be able to get 10-12 pops this season. Training pressure will give a pop every 1 and a half weeks, but it is finnicky. Try to gethis OD up to sensational at least. Sometimes you're lucky but not always. Training pressure is best at a young age. Also give a couple of weeks in JR as that is also a slow skill to train. Try to get it at least to proficient if not prominent. During the remainder of the season if you have time and for a large part of next season train up handling, passing and driving as well as an occassional jump shot. These train relatively fast so can be left till he is 19. By the age of 20 he should be a pretty good PG and then you can just polish and improve all his skills, especially JS.
If possible upgrade your trainer. It helps in the long run.