I don't like the stock strings however (Epi uses D'addario or Ernie Ball rounds as stock strings) because I like flats better, but rolling off the the knob gives the bass a close-enough-to-flats sound for me.
I doubt they're either of those two companies - I got a JC Silverburst as my Xmas present, and within 10 minutes I was getting the
"Nasty Black Smudge" on my fingertips... and I have the
opposite of string-killing acidic hands (I can go
months with Steels unchanged at about 80% of Zing! remaining.) I also had the same reaction when I purchased... and quickly returned an Epiphone Special Edition Silverburst Thunderbird a few years ago. Generally some low-a** funky strings!
(which I quickly switched over to my fretted bass D'Addario ProSteels, which I figured were close enough to Jack's recommendation of Dean Markley Blue Steels)
Black Hipshot Supertone bridge, black Hipshot ultralight tuners and black Rotosound tape wound strings. The silverburst has grown on me. With these mods, awesome.
Dude, get
out of my head! with the Black-on-Black hardware concept for the Silverburst!

You could go either way with it, but I'm generally a black hardware guy anyway, and if I'm going to be upgrading those parts I'd rather match to the 'burst & added black parts than the Chrome. When I told my Tech I was going in that direction, he practically shouted
"Oh my god, you have to do that!!"
Whafrodamus, this Bass is truly Beauty and The Beast! The interesting thing about you wanting a P-Bass before this is that I personally find that when I'm using my Casady in "Electric"
(aka Vari-tone @ "500", Tone full and Roundwounds) it's pretty close to the fullness of a P but with more mids than I typically hear in them. But roll the Tone back, go to "50" and playing with flats or a light touch and you can easily do an Acoustic Set with it. I've got some truly nice basses, but I believe the Jack Casady Signature has them all beat for sheer usefulness!
