Understand really hit for a big, slow first baseman means a constant threat to hit one out. Slow runners clog the bases if they’re not clearing them. If he wants to play D1 he should be thinking pitching with his size and potential to improve his velocity overall the next couple of years.
Given you don’t see him as a pro prospect you may have the process backwards. What does he want to do with his life? What does he want for a major? Where does he want to go to school? Then cross schools of the list for lack of a quality baseball program.
He needs a business plan with target schools. Don’t throw spaghetti off the wall to see what sticks.