In the video that TPM gave you, notice the front side glove on that player. You lose much when you drop the glove hand as you do, look into the concept of "equal and opposite. Also, skinny or not, your bottom half is passive (Along for the ride), power is derived from the ground up. It is very common at your age to be as fast as the arm can get you, without integrating in that lower half, you'll be trapped at max arm speed (Usually low 80's).
I think you are creating your own hurdles, Canadians have a solid spot in the majors, somehow all those other guys worked it out...I'm sure Fergie Jenkins didn't have even indoor facilities..maybe not even Ryan Dempster..so desire is the thing..if you want it bad enough, you'll find a place to work and maybe a protein shake or two to add a pound or two to your skinny self.