Here is a subjective list of top 10 Current MLB Pitchers & College / HS.
Kershaw- HS
Arrieta-College
Syndergaard- HS
Bumgarner- HS
Strassburg-College
Felix H- HS
Price-College
Sale-College
Fernandez-HS
Cole-College
Fairly balanced. Interestingly, I may be missing it & probably am, but out of the College crew, I only see Sale as drafted out of HS in the 21st Round. Strasburg, Cole & Price were all overall 1-1 picks in College having not been drafted in HS. This alone displays the huge potential upside to HS pitchers.