Maybe change some on hit effects to be time based and not every X hits

Like how GotU works. It would be much simpler to balance around since it would not be limited by each champions attack speed. Champions like Yi and Kog' Maw who have attack speed self buffs could still work with it, but would be able to merge into the norm a bit more (adc builds like a standard adc, and Yi would be either tank or full damage, not some hybrid with 2-3 items of each, while still maintaining his damage if tank and be allowed to utilize the on-hits less because he has the damage to do so if full AD).

While it is not limited to those two, it would have larger effects on them. Just an idea.