The subject of the shop has been discussed to death, but one that I don’t think has been is the issue of recolors.
Operative cosmetics should allow you to recolor any armor you’ve gotten, be it penance or bought at the store. As it stands some penance armors can’t be recolored, and premium cosmetics can’t be. I’d like to be able to buy armor that I think looks good from the shop, but change it from blue to green, etc, to look the way you want.