This would hardly fix the balance issues with crossbows. But even early game, the combo of armor piercing and being able to hit mutiple targets feels strong without any min maxing. The early game weakness of crossbow quick shot, aka blocking and high hit points is balanced out by slow death being rather good at dealing with those, not perfect (until you min max it)
At 80% quick shot damage, crossbow quick shot would be good for picking off armor targets or weakened units, but be not so good indiscriminate slaughter until you either add mutihit or some kind of major damage boost to it. It would feel balanced to a sort of amateur player that has a general idea how the game works but not good at op combo yet.
Basically I want the cross bow quick shot to feel a little weak without extra mutihit or maximized dpr, but still usable.