I've used 600-grit wetsandpaper (the black stuff) on the backs of all my electrics for years, decades, actually. It's enough grit to just "break" the surface of the finish and offer a smooth-and-slick playing surface. The paper loads up fast so use light hand pressure and go easy; a little sanding does much in feel.
FWIW, I've never felt the need in my acoustics, but for the electrics, this is my SOP. Once done, that guitar is good for several months of regular playing until I feel the need to break out the paper again. Simple and effective.
Edward