I DID base the finish off what was used in Civil War, but I'm not a fan of the claw marks (main reason why I didn't invest in the Masterworks edition shield).
However, if I had a few more of these, I would definitely refit them to other styles used.
After seeing that you did with this shield, I bought 2 pcs. On ebay the only thing that is off is the star piece is not accurate the lines are too thick and the lines from the middle should go all the way to the edge of the star not to the boarder. Im thinking of filling first the star lines with bondo and etch a new one using a cutter and ruler. I will probably do a Avengers (2012) efx one and the broken shield from endgame ( skeptical about this one)