from a 501st perspective, i doubt they are going to be concerned with quite the level of detail we aspire to here.
i think that as long as you stick to the same general colors (for example, the back of the ESB one is a blue-green sort of color, so something in that vein), and keep the "signature scratches" in place, you should be good.
by signature scratches, i mean the things that really jump out. for example: not many people are going to notice if your dent is 1/4" too large, but they will notice if you don't have one.