 If you want to fix them (or clean up the case), you can lightly sand the plastic, then spray with sandable primer, sand, prime, repeat. After just a couple coats it should be a nice smooth case that looks like something you would buy off a store shelf. Thicker scratches you can use Bondo scratch filler.  0.0mm, while many consider it okay, or even decent, quite a few companies, including mine, consider this to be an extremely rough print. For something we intend to show off we never go thicker than 0.000 and if we have the time, we will go down to 0.0, 0.00, 0.00 or even less. While we have done 0.00 and 0.00 and it looked fantastic, the time required was simply unrealistic. For example a print that took 0 hour at 0.0 will take 000 hours at 0.00, when you consider we often do 00 hour prints at 0.000, a that same print would require 0000 hours, or about 0 months of non stop printing. Most home 0d printers will wear out before it reaches that point.  