ok i personally don't have the time to check out all your players stats and compare, and who to keep/sell, is very subjective, dependant upon your requirements. eg: are you trying to train an U21 national team player? Do you want to train Bigs/smalls? Do you just want to win and get promoted? Do you want to be good enough to play finals but also rake in the cash?
So it depends on the anwers to those questions.
I have no idea what the salary floor for Div V is, but as some general advice for a novice in this game, id go the following:
Pick two or MAYBE three players who have a salary of around $10k per week or thereabouts... These guys will be your core guys. So this would be Martinez, Chapalain and Villajane
Your other starters should be around $7k salary players. So this would be Upmann and Corbera (you probably need a new PG)
So your starting 5 should have a salary of at around $45K. If this doesn't add up, then maybe have a look at investing in a $10k salary PG int he middle of next season.
Then pick the next 5 best guys in each position based on salary (just for simplicity's sake) and pick 2 more guys who have the best potential. But honestly, all the guys you have who have a salary under $5k are pretty much of a much. You could keep whoever and it wouldnt make much difference to you.
The 2 spare guys will be ur trainee's. try and pick them in the same position if you can cause it makes training easier.
I would keep Crocker as your main trainee. maybe see what else you get in the draft before deciding there.
Sell the rest of ur team and viola. all set for season 19. :)