Polishing should be the absolute last step unless you have a polish that you know contains NO wax. If there is any wax on a surface you cannot do any repainting or touching up. Many polishes do contain wax.
I was wondering about using pumice as a polish. I remember a woodshop class in grade school where we used pumice to polish a varnished piece of wood. We used oil with the pumice, which is also not good to paint over, but at least it is easier to remove oil from a surface than wax. But, I wonder if water would work with the pumice. Do hardware stores still sell pumice?
I know many friends who use lacquer on model race cars- I have used it occasionally. It polishes out very nicely. I mean the real lacquer, not acrylic lacquer. Doesn't go down as glossy as some model paints but sure polishes nicely. Used to be common in real car auto parts and paints stores, getting harder to find.