"Phantom-Hit" passive may just be too hard to balance.
It is just too easy to abuse damaging passive on-hits to compensate for not building full damage builds. Basically treat it like vayne where you only care about how frequent you can attack rather than how hard you hit. Quantity over quality and such. But having that type of passive synergizes with too many unique and different champions and is compleatly worthless on others. This is a tricky problem where finding a balance may infact be impossible and just nerfing it might make it not worth purchasing at all because it can't cover other damage sources in terms of offensive power.
Back when the passive was on devourer, it synergised too easily with the attack speed you gained from devourer and other items which also had on-hit effects such as rageblade and bork. But with the passive moved onto rageblade now, you actually might have just cut out the middle man and made the "brokenness" of "sated rageblade" become easily acquirable on a single item without having to take smite. While this may or may not be game breaking, it certainly is not a step in the right direction, at least in my opinion. In addition, with the added bloodrazor passive of 3% max health as physical damage on-hit effect, I feel that the power was actually increased instead of rebalanced, and at a cost of only a few extra pieces gold more.
It is a bit concerning that the very item synergies that "broke" many champions such as Master Yi and Xin Zhao, have been made easier to acquire and even possibly boosted in power from its original state. To me this does not seem like balancing at all and more like buffing the champs since even though they are abused in lower elo ranks, they rarely see competitive play because of their basically straightforward build paths and limited kits to play around outplays and team fights. For example, if you see a Yi you already assume he will have sated devourer as the jungle item, and then get rageblade or bork or some other good on-hit item and then go on a semi-tanky/bruiser like build path. And I feel it contradicts the recent Yi changes which were meant to force him to get an additional offensive item to have good damage output. Since the 3% max health is very nice when paired with phantom-hit, he already has good damage right there.
I would rather see phantom-hit retired or at least disabled for further testing around how to balance it. It is a cool passive but I feel that it may just be too hard to balance effectivly.
EDIT: So were all clear, this is not a post about rageblade. It is only looking at the phantom hit passive, which now just happens to be on rageblade. I used rageblade as an example to show synergies commonly used with the phantom-hit passive and because it is what the passive is now on. The focus still being the passive not the item as a whole.