For jumping, I do think that requires that much more upper body control and accuracy for the rider because the horse is less able to accommodate a rider jumping up on their neck or tipping forward. As someone who owned a 16h mare with a mega barrel and mile long neck, I learned that loin and neck connection made much more of a difference with handiness. A horse with a short and nicely set neck can ride much cattier and lighter than a long-backed horse with a short low-tied neck. To me, the gray looks like that combination of poor loin connection and short low-tied neck.
Personally, I think you look very tall on the gray who looks kind of weedy and lacking substance. Also, my opinion really doesn’t matter. If the gray is the best intersection of brains, athleticism, soundness, and rider comfort in your budget, then it makes it a smart purchase.
