The easiest way to balance any prop is to do it while you ream out the hole. Start by doing any finishing that you want to do- scraping the burr from the TE, removing mold lines from composite props, painting, polishing, etc. Use a tapered reamer, and shave a thousandth or two off the side of the hole with the heavy blade. You don't need to remove much material. Take a little off, then ream it just enough to make it round again and check it. I also do the hub if needed at the same time. That means if there is a heavy blade but it's also tilted to one side, I'll attack the hole toward that heavy hub side. A round file is a better tool for removing the material, but isn't required. So 3-4 cycles of making the hole oval and then round again will yield a perfectly balanced prop with no sanding, no glue, and no paint. After the prop is good, ream the hole to size for your engine. I use a tapered reamer for that as well. No, it doesn't hurt anything as there is zero stress on the sides of the hole after you tighten the prop nut.