Excellent question! The use of black skin started when a fellow in Japan, Kiju Kitamura, found he could dye Ripple (he used to skin the Eclipse and Akatsuki with Ripple for us before I released Hibiki). That started only 3 years ago, and while quite a few players fell in love with the color change (as I have), white is still the standard for many in Japan.
Even in the tsugaru shamisen tournaments, non-standard materials (acrylic bachi and non-white skin) are looked down upon. An interesting story - Reigen Fujii is the champion of the Aomori tournament and has literally a closet full of first-place trophies from dozens of shamisen tournaments. However, two years ago, he competed with translucent acrylic bachi and didn’t even place.
I’m planning to compete at the Hirosaki tournament in May, and because my shamisen’s skin is black, I’m not expecting to place at all. But my goal isn’t to win, just represent the international community.
Oh yeah, red would look super cool! (Or perhaps a burgundy?) Perhaps we could add that!