When you do paint it, give it a good rub down with a rag and alcohol, let dry, then just dust it very lightly with spray paint. The less paint the longer the finish will last under heavy use. I would do a light wash to bring out the detailed lines, then just wipe off the smoother surface of the wash. The lower areas will retain the color. Let it dry then dust it with matte finish. You could at this point do another wash of a lighter color. If you do that and add a thicker coat of matte finish, you will get some weather beaten pit mark looking areas.