How valid would it be to use on every non-repeating crossbow?
+1 - Quick-loading: Dimensional pocket with 100 bolts, move action to reload. 
+1 - Self-loading: Reduces move action to free action. 
You'd be able to shoot any crossbow that doesnt depend on a magazine without needing to reload it yourself. Quick-Loading would make the bolt pop into existance on the crossbow, and Self-Reloading would make it pull the string back by itself.
That would let you full-attack with any crossbow and never think about reloading it ever again in your life.