Personally, I would sell all my guitars but the one I play most and my most valuable. Truthfully, you only need one. Keep the one you play all the time. The other most valuable guitar can be perceived as an investment if you're willing to hang onto it long enough, so I'd keep that one too. I don't need the cash so I haven't sold any, but I feel so wasteful looking at the excess of gear I have. People are starving and I'm hoarding guitars and amps for no reason.
As for your Washburn WM526, just sell the guitar. Every few years you go through this same dilemma with that same guitar. You've talked yourself into liking it more than you actually do just because of the one-off paint job. That is no reason to keep a guitar, in my opinion.