FQC just needs to not be usable for mid-laners/mages
Honestly, just let it only be usable for the mage supports that it was designed for
It's fine when only one person (or only one person on each team has one), but when literally 2-3 people are building on a team then it just becomes a major annoyance having to be slowed literally all the time
There was a change implemented that made the active not usable for an amount of time if someone CS'd, but then you ditched it for the nerf that we have now