Re: Pickup for PRS Custom 24
Fat, tight, & clear in Seymour Duncan I'd probably look at a TB-5 Custom (perhaps swap the magnet to A8 if the ceramic is too bright). Screamin' Demon also fits most of that, but probably not quite hot enough. [Or if you want more vintage output/tone, a '59 Bridge or Whole Lotta Humbucker, depending on how much you emphasize tight ('59) vs fat (WLH).]
The PATB-2 Parallel Axis Distortion might be another option, it's an amazing gonzo metal pickup. Not the tightest, but very fat, massive growl, singing leads, crazy sustain & harmonics, and one of the hottest passives Seymour Duncan makes. Might be excessive output and less flexible than you want. Surprising amount of pick articulation, but it turns up more as tone change than volume, given any amount of distortion. Massively fun pickup to play. I've heard people play thrash on it, and it was definitely better for leads than conventional Distortion, but took more effort to keep under control for rhythm.
Outside of Seymour Duncan, Railhammer Alnico Grande seem to fit the requirements particularly well. Wound strings are tight because of the rail, plain strings fat thanks to oversized pole pieces, it's wound pretty hot, but still can do a wide range of styles. Kind of like a Custom 5 with more mids and output.