So, I would look at this from the college or pitching coaches perspective. What would they be looking for? Sure your son projects to mid to high 80s with a potential upside to 90 by the time he gets to college...best case scenario. Velocity is important but there are many other factors that come into play for potential college pitchers. For example, I'd be looking at his control, secondary & tertiary pitches and movement. These are the things that separate pitchers at each level in college baseball....and there are many levels. So those are the things he can control as a pitcher.
College is different than high school. In many cases you get to pick where you want to go. BLD gave you a list of things to consider. My son researched the heck out of the schools that were interested in him and offered him. He is kind of a math geek so he was looking at a lot of numbers and figuring out where he thought he could crack the starting lineup and the type of environment that suited him. He figured out artificial turf was the surface that best fit him because his best pitch was the change-up and cutter that resulted in ground balls or doubleplays when he was on his game. Like most college pitchers he had velocity but used it to his advantage when he needed it either in on the hands to righty hitter (in cold northern weather) or out of the zone to a lefty....and it had movement. These were environmental factors that helped and complemented his game.
Another thing my son and I looked at was the medical history of the rostered pitchers over the last 4 years. Pitchers get hurt. It is a fact of life, however pitchers tend to get hurt more than others. So we paid particular attention to that aspect. Son found one school that offered him to have an extremely poor record of protecting their pitchers arms. He crossed them off the list for that reason and other reasons. So, I would take a look at that as you dive into each program. Read the bio of the players and determine how many took the season off because of injury.
As you begin to have conversations with college pitching coaches, ask about their strength and conditioning program. These programs vary considerably, and it can be a huge determining factor in his college performance. Strength and conditioning is important. So is nutrition, and flexibility especially for pitchers.
There are so many types of colleges and so many types of baseball programs. This website (through it's members feeback) can help educate you and determine on the "developmental" programs vs the "highest level you'll play and compete and get a good education" (your words). However those input factors have to come from you. You and your son have to figure out what is most important to you. Once you figure that out the HSBBWeb board can be an unbelievable resource with practical knowledge about many college baseball programs.