It's your weapon, decorate it to tickle your fancy. I have two M1 Garrands and had both restored and duracoated (no flaming, please). I did this because they go to the range a lot and were intended to be shooters. I did not buy them as investment guns.
I never understood why you can buy an old car and resotore it and your actions increase its value. But, restoring guns decreases their value.