I just read your note on wanting to throw a curveball. I’m from the “real old school” of baseball and if you want to throw a simple , good curve ball you may want to try the 1940’s 1050’s knuckle curve ball, it really breaks over and down, and there’s really no strain on the arm. Here’s how:
Hold the ball with a two seam fastball grip, but a little deeper in the hand, Now put your middle finger just above and touching the seam, and curl your pointer finger so the fingernail is resting on the ball. If you throw this pitch like a fastball, you will get movement to the right if your a righthand pitcher and movement to the left for a lefty.
Now, if you use the same grip,and turn your palm in–toward your ear—and snap the wrist down and pull the middle finger in you will get a down breaking curve. The finger action is like shooting a cap gun or dart gun, but your using your middle finger to pull the trigger instead of the pointer finger. A pitcher who pitched in the 30’ 40’ showed me this method in the 1950’s when I was a freshman in High school. This kind of knucklecurve really breaks great when you get it down and it wont hurt your arm. As with any new thing dealing with ‘muscle memory’ start out slow and just try to see the spin on the ball, and gradually pick up the speed, it might take a couple of weeks or so but you’ll get it down with pretty good control. Hey! give it a try see what happens. Hope this helped you.