I have a guitar with 85/15s and usually run the guitar volume at 5-8 with it. I feel the pickup’s frequency range sits in great balance set there with my amps, and I do adjust the amps for each guitar, too. Again, the interaction of all guitar and amp controls is what I’m after.
Also, if you start with the guitar at 10, you’ve got less ability to control solo volume/gain from the guitar, when you want more.
Watching great players using the guitar controls constantly while playing to milk tone nuances from their rigs was instructive for me. YMMV.
I like the 85/15 for certain tones and textures more than the 58/15, though I have, and like, both. The 57/08 might be my favorite conventional humbucker, but it depends on my mood, too.
The Paul’s 408s are gorgeous sounding pickups, whether playing clean or dirty, and I run those with the guitar 5-9 or so, most often toward the 5-6 range.
But all this stuff is personal.