I don't yet have the Vet reward jacket (ETA ~35 days), but I would like to be able to fully edit the colors.
The same goes for the Ambassador's Diplomat jacket. There main part of the jacket itself is white, can't be changed. I don't mind that so much, but there's a trim that's a light goldish color that can't be matched with the existing color pallets. The jacket does include an undershirt and piping that you can alter, but again, you can't get it to match the trim.