I see you're from San Diego. At this point, no need to spend money to go anywhere.
There is a PC in Poway who has a stable of over 100 pro pitchers (many are cracking MLB) - most of whom have been with him since college or before. His goal is velo. Go, sit in his Back Yard, and see for yourself. (Right now the program is in full swing so your son may get a kick out of just watching the scene. At this point it's 7 days a week until the men begin heading off to ST.)
I could fill a page with what I think, but he'll explain it better - Jeager v. Weighted balls v bands, etc.. Let's just say he took my S in ninth grade who was low 70s, 5' 3" ish and 115, and turned him into a HS senior throwing 90 (5' 11", 140 as senior), with no injuries, lots of fun and mentoring (S is now retired and still keeps close touch). S was not an outlier result.
We spent five days a week during HS driving from downtown out to Poway (his program has a great physical training element [Hoefflins]), continued training whenever S was in town during college, and through his pro years.
Tremendous pro and college connections (every type of college, from JUCO through IVY league). My S had minimal showcase and travel ball exposure; just pitched in the Back Yard and the exposure came to him.
On top of that, as a person who cares about the kid (not just the baseball part), you'd be hard pressed to find a better mentor.
So, go see for yourself; doesn't matter which program is great (and there are many), unless your S bonds with the coach and wants to be there, there is no point.
Feel free to PM me for details, if you're interested.