Are you training to sell, or training to play in your team.
Either way, i think the 17 year old is of little value now. Wouldnt make many teams, and for a 17 yr old he isnt too good (most other have been trained all year).
Plus most people have thier own.
Id get the 19 yr old up in strength, should have 2 pops in him before season end. Put the other one on passing till he gets to 3, and then handling till he gets to 4.
Would sell for slightly over a mil for a 20 yr old 8 strength, 5 tackling, 3 passing, 4 handling.