I think you should be in good shape. SF is one of the best positions to get a highly talented player without an obscene salary. My SF Marrinan, admittedly is close to being capped as a Superstar potential, but he has 106 skill points distributed (not including ST or FT) and should be on a $60k/week salary next year. Which is expensive, but he'd do some serious damage if put in a lower division.
In short, train him right and don't overtrain the high salary areas; for example popping his JS as high as it can go won't make him a great player, but his salary will increase greatly.