Wow, sounds very close to my son..... almost too close. Just kidding. My son was also 6'1 and 140 at 14. Now 6'2 and 165 and will turn 16 end of Nov. In my opinion keep pitching, get a good coach and go once a week or every other week. But try to get stronger overall, core, legs everything. I can't tell you what a difference the added weight and strength made in my boys body control and mechanics and therefore his velolcity increased a lot. Plus it increased his confidence and overall attitude. I would say run, run, and run some more and just add a good overall strength program.