What kind of champs are Press the Attack actually meant for?

So Press the Attack keeps changing wildly on PBE, from gaining AD/AP per auto, to gaining AD/AP per auto and a %damage increase after enough autos, to dealing true damage every 3 autos and a smaller %damage increase after enough autos. Press the Attack is for champions that auto attack a lot obviously, and champs that will be auto attacking the same target consecutively especially. So Press the Attack is appealing to 2 types of champs:

1)ADCs, who have lots of attack speed and have extremely high stat efficiency with AD because they buy infinity edge, their autos scale with 250% AD not 100%, they can stack Press the Attack insanely fast. and 2) bruisers with sticking power, who prefer long trades, extended exchanges and constant all-ins. Champions like Jax, Darius, Olaf, Irelia, lots of top laners. These champions engage in extended duels where they'll trade tons of autos in between abilities, and they'll also use lots of abilities which will scale with the stats they're gaining from Press the Attack (obviously they don't scale as well with the new true damage press the attack because that's for champs with high AS only now). They'll also benefit highly from the %damage increase because that means an increase in the base damage of all of their abilities.

But these are two very different classes, and they want the same rune for very different reasons. ADCs want it solely for their auto attacks, because their autos scale harder than any other class' with AD. Bruisers want it because they weave auto attacks in between their spell casts, they cast spells that scale with the stats it gives frequently, and their spells typically have high bonus damage or %hp damage. The newest Press the Attack (the true damage one on PBE now) leaves some bruisers out in the cold in terms of viable rune keystones now. They're going to be stuck with grasp, which will be better on tanks, electrocute, which is for burst mages and assassins and is suboptimal, or phase rush, which not all of them really need. Tanky DPS has no real damage keystone anymore, and it sucks to see the DPS tree become the marksman tree. If anything, I thought Press the Attack deserved to be for bruisers and not marksmen after seeing the second iteration. Press the Attack is all about continuously attacking a single champ, but marksmen kill everyone in 3-5 hits late game anyway. I think the second iteration made much more sense as a bruiser keystone for champs that like to alternate between autos and spells frequently, increasing their auto damage, their ability scaling, and their base damage/%hp damage all at once. ADCs already have lethal tempo and fleet footwork, and now they've forced a keystone great for tanky DPS/bruisers to be for them instead and the fighters and bruisers will be maligned into taking grasp or possibly phase rush.