4 Arms:
The next level requires "quicker" reflex. Do you realize the ground ball speed off a metal bat from a 19 year old hitter and a 15 year old hitter?
When I tested SS I use the "range" work with a 37" SSK fungo. Left, right, right left, one hop, 5 hops. then double play with the 2b.
Play where you can learn the game and improve your quickness. When we traveled Internationally I selected 4 shortstops and moved one to CF, one to 2b and one to 3b.
Bob