Nerf the interaction, not the champion or the item

In this game items can be nerfed if they make certain champions OP or a champion will be nerfed if an item makes him OP. This leads to the problem that the nerfed items can become unvaiable to build on all champions or if it is a champion, the the nerf might negativley affect other builds for that champion as well so what i was thinking was to implement a control system for the interaction between champions and items where the items have a maximum and minimum value for each stat or effect that they give. For example and just for explanation purposes, with and both using it could be made so activates "phantom hit" every 2 to 4 basic attacks depending on the champion using it so if uses then the control system makes it so it takes 4 hits to apply "phantom hit"but if uses then the system can make it so it takes only 3 hits to apply "Phantom hit". Its a simple idea but can be quite difficult to implement and it could potentially be a solution to the problem where a champion is nerfed because of an item, the item is nerfed because of a champion and and in the end we end up with a weak champion and weak item.