Selling great guitars hurts and I've swapped some in my day...not nearly to vaijem777's standards, few of us can equal that!!!
I view them more from a utilitarian perspective. I don't have any guitars that sound alike tonally, they all give me different textures, some more subtle than others. I think I've got a good smattering of tones and, for now, I am satisfied with my collection.
The VWH is just a all out freakin in your face rock machine, but that neck position is awesome with my boogie for the bluesy thick-toned sounds.
The UVPWH, other than the low B, has a much fatter tone than any of my other guitars. It's scooped and just huge sounding....again, love the neck position. This has the most "Les Paul" sound but without all the mids.
The JPM-P4, loads of sustain, completely different sounding due to the pickups and the switching. LOVE THAT NECK!!!! This guitar excels at just about everything, and clean it is nearly unmatched.
RG-ART: This thing is like looking at a naked lady...you just can't stop. Tone wise it is more similar to the JPM but has more snap to it, must be from the very thick top and the maple neck. Articulation in the sound is unmatched and it is extremely balanced across the tonal spectrum. Simply an amazing instrument.
Maple necked strat: This one has an alder body, fralin vintage hot pickups and a callaham bridge. It's classic strat, the pickups rule and the bridge adds an incredible amount of sustain and clarity...probably the best money I've ever spent on guitar equipment (all of $95!!)
Taylor 714CE: the most beautiful thing I have (other than my wife and kids)
Yamaha Silent Nylon Stringed Thing: Great practice guitar/toy that sounds incredible plugged in. This thing is just fun, fun, fun...gotta get to learning some flaminco tunes.
The only thing I would add now is a hollowbody jazz box of some sort to round out the sounds.
I guess the point of all this is to say that if you approach buying and selling/trading from a "what tones can I add to the collection" it takes some of the sting out of parting with a great guitar. It also ensures that you play what you have more consistently. If all the guitars in your collection give you a different voice, then it will inspire you to play more creatively and expressively to bring out the best of those voices. Blah blah blah.....you get the idea. At any rate, that's just my take on making sense out of all the buying and selling. My wife gives me tons of grief about it, mostly in a poking fun sort of way (she's actually very supportive) but I tell her that guitars are for me what shoes and purses are to her. You can't wear the same pair of shoes with every outfit!!