I love it, but I'm biased... it looks like our "Track-a-pult" has a twin of sorts!
You throw the ball quite a bit farther (thanks to your primary use of surgical tubing rather than our motor+surgical [2cims and 2fp]), and definitely have better programming, but otherwise we're very similar. We even had the same problem with the ball rolling forward in the gripper forks during launch (seen in the slowmotion clip).