Idea for a new way to balance items: requirements

An aspect of league that currently hamstrings the balance and gameplay teams are unintended item interactions. It seems like there is an obvious and elegant solution that has been used sparingly, but could be made an "official" part of itemization: requirements.

On items with requirements, it would list requirements as part of the cost so that it is obvious to players why they can or cannot purchase the item. Here are some current examples of requirements already in the game:

, melee, ranged, no existing gold item

I suggest adding additional requirements: Possess X completed item (or item type) Class tag (assassin, mage, support, tank, marksman, fighter, juggernaut, diver)

Then you could easily make an item for supports, for example, that toyed with lane experience earned, but it would require you have a sightstone and the support class. You could make an execute item that only assassin champions could purchase. You could make an AP item that only mages could use, etc.

Just a thought.