Do an inexpensive local showcase to get his measurable metrics. Then figure out what needs to be improved the most and what direction to take. If he was ready to showcase people who have seen him and know the game would be telling him. Being strong defensively is nice. But baseball recruiting starts with driving the ball consistently. Right now your son should focus on getting bigger, faster, stronger and more skilled.
To be honest if he’s throwing out several hitters at first base from the outfield I have to question the competition he’s competing against. It’s a very infrequent play once past 13u.