Hi en welcome!
- To answer your last question. BKP's keep clarity, dynamics and stringseparation under highgain and don't mud up. That's why in the beginning they seem to 'lack gain' (a pickup doesn't have gain, but I know what you mean), but they can handle tremendous amounts of gain without mushing up, squealing or producing false harmonics.
- PRS: There a quite some PRS-users on the forum who will chime in sooner or later. The Holy Diver will fatten up things, but this one breezes '80's-metal. Can do some classic stuff too. Personally I think you should have a look at the Abraxas and the Crawler (a hotter Abraxas with a bit more compression). They both have a warm tone, with quite some mids and a round topend, the Abraxas having a bit more PAF-chime in the topend. The Abraxas is alnico IV, the Crawler alnico V (neck is IV though). Both have a dc-resistance between 14-15.5 k.
- Gibson: Nailbombs to me breeze 90's-metal. Maybe they can do classic rock, but I would not rule out Mules, which are wound after the or. 59-PAF's. Mules are really versatile (Kravitz use them too) and can do metal if you like. Black Dogs are an option too, with a more focused midrange.
Just my 2 cents