Re: What upgrades are you guys doing on Les pauls?
My LP's are Epi's. I've upgraded PU's in them: Seth, A2P, Brobucker, UO C5, Fralin, Burstbucker, 36th Ann PAF, Smits, & Parsons Street. Also use some hybrid HB's I've made, which have A2's or UOA5's in them (both bridge and neck hybrids).
They all have an alternative wiring of some sort: Jimmy Page System, spin-a split, or Artie's coil swap mod. They have either a neck hybrid, or an alternative wiring that gives unbalanced coils in the neck. I love LP's, but want a sharp high-end on their neck HB's that only unbalanced coils can give. I don't like warm/muffled/boomy neck PU's in anything, and LP's are especially prone to it. I've tried PG's and '57's, ended up selling my sets of both. Their necks are too warm and I couldn't get the tones dialed-in even with magnet swaps. There's better PU's out there, and especially now that I'm making hybrids, I don't have to settle for PU's that only sound 'okay'. At this point, any additional LP's I get will have hybrids in them.
I also have a couple LP's with P-90's, and in them I have a push-pull to link the PU's in series, for a volume boost for solos.
I warm LP's bridge PU's with either 250K pots or a 470K resistor. Most of them with neck HB's (as opposed to neck P-90's) have one or two 1-meg pots (the other neck pots being 500K). The wiring, toggle, and jack are kept stock unless faulty.
For me, this is how to get an LP sounding it's best. High quality PAF's or hybrids made from high quality PAF's, spin-a-split on the neck with bright pots, and warm pots/resistor on the bridge. Taken me years to fine-tune the formula, but I've finally got it.