I believe the intent is to lightly push them into the foam. Stagger them as you wish. Likely I could fit nearly a dozen 2-blades in there, but I only have 6 hunting arrows. No concern as to the aforementioned sliced knuckle as you grasp them by the shaft, say maybe 3-4" back for removal. The normal "draw" won't put an edge antwhere close to your hand.
On an older stalker I have from High-Noon-Hunter, I would just let them sit in the cup on the surface of the foam. Never had a problem.
Keep in mind, what you are using is essentially a "back quiver" with a fancy draw option.
Just My Opinion. Lets hear others.