In my mind I figured the best way to update part textures is to have an extra tab in the VAB that lets one select parts on their craft and pick out different skins for tanks, engines, and such, without modifying their position or function of the part itself. The placing of attachment points and the width of the part would have to be kept standard, but otherwise, there is nothing stopping the parts from being reskinned at will as far as I can see. Instead of just having the X-32 tank with only its heavy banded, riveted design, or the X-16 with its strange(ly pool-like) crimped texture all down the sides, why not add variations so they can all be crimped, or all banded, or [x] or [y] texture consistently, or any other combination? People like nothing more than to make their rockets look exactly the way they want, after all.