At the very least, even if you don't keep him in the Majors, You should definitely invite him to spring training and play him in ST games. I do this with all my top prospects. Spending time with the ML coaches is beneficial to them.
One question: how many years of pro experience does he have? If he's played 5 years already, don't expect any increases in his ratings, regardless of what your advanced scouting says or where you play him.