The question seems clear enough, but I want to clarify a thing : lots of champions who would benefit a lot from Guinsoo but who get little to nothing from AP. I know that that the item was designed for hybrid autoattackers, but since you made it the hyperscaling item for on-hit build, it would make more sense to have only stat that the champions who use on-hit effects care about, wouldn't it ?
Edit : I am speaking of the 6.9 Rageblade.
It actually makes sense as many AD champions have 1 or 2 skills that have so kind of AP scaling, which seemed useless, now they can get some kinda use to it.
Name one champion that bought Guinsoos that isn't an ADC that doesn't have an AP scaling that gets taken advantage of by the AP on Guinsoos
I'm pretty sure the idea was to make it less efficient on those who only want the on-hit.
There's a lot of champs 
who already liked rageblade before devourer; it wouldn't be fair to leave them all in the dust for the sake of a few with no AP damage scalings.
I can only think of 
and 
that were building it but didn't really use the AP,
and 
built it but liked the AP as well.
