In reality, ONE good JS player of coz can score a lot, but most of the time PG holds the ball, PG can make a magic pass to one of FOUR players in court to have easy scoring.
For example, ONE good JS player can score 30+ in a game, but he may need excellect stamina to do so. Relatively, ONE good Passing player can help other four players to score 10+ in a game easily, not much stamina needed in average, that means delicating 10+ assists & 40+ points totally.
In conclusion, i would prefer a good passing player instead of focusing JS ability during training.
P.S. above personal assumption is based on reality situation instead of BB game engine.