With the two players you have listed, you must try to keep player 1 as well rounded as possible to get the most out of his cap room, which is a little limited.
I would tend to agree that JS for forwards and IS are generally the two areas that need to be worked on the most. It's something that should be worth nearly half a season of dedicated work, as both guys could get 2 pops in JS and player 1 needs about 3-4 pops to be a worth mid tier SF.
The biggest issue you face is that player 1 and player 2 will both turn into SF's if you continue to work on them both. Not sure player 1 can put up the offense to slide into the SG spot, not sure he can pass enough to be a PG, and while he can be a nice SF with maybe 12 or 13 IS/ID and 10+ perimeter skills save for JS, i think Player 2 is significantly further ahead.
Other training i think that player 1 would need is 1-2 one v one to improve driving, 2-3 OD to improve perimeter defense, and perhaps all out offensive work rather than passing if you want to try to turn him into an SG with every bit of cap room he has available.