Are you injecting the Prop daily? Even 10mg of daily Prop wires the hell out of me. Back when I was injecting straight prop, I was at 8 daily with over top of range results.
My two cents is that you may have to stay within physiological levels to see sleep improvement from the overnight trough of straight prop (or a blend for that matter).
Very interesting note on libido with Prop. Unfortunately I did not experience that maybe because of my lower doses.