As an idea for your cash shop, try taking an idea from CSGO. Call it "Engrave" Make it cheap, such as .99 cents or a buck fifty. Cheap will keep people buying them more often. Obviously the name can be the same to avoid confusion but just have the name in italics below the real name. What it does is it lets people give their favorite weapons a little flavor. I'd pay a buck to rename my favorite daggers to "Gooch Trimmers". Anyways, at a glance to an non-developer it seems easy to implement to me, but what do I know. If it is, its small investment for a decent gain.