While I like the idea of a new crafting class, what concerns me most about these ideas is that they (with the possible exception of the tatoo artist, more on that in a sec) seem to be exclusively geared toward furnishing-type content. This has two big problems: First off, furnishings currently provide no stat bonuses or other benefits other than to look pretty in your home. This means that every creation is a luxury item, something people will only buy if they have the spare money to do so. Secondly, folks who own houses are a pretty small fraction of the population (though, admittedly, they're a small fraction that is more likely to have extra money for luxury items). That's an awfully small minority to devote an entire crafting class to.

As for the tattoo artist idea, this has some promise - particularly if we allow for the possibility that they are MORE than just pretty pictures. You mentioned using Materia to affect the appearance of the tattoo, but what if tattoos actually had stats? A tattoo could be, in effect, another gear slot. There would need to be invisible tattoos available for people who want the stats but don't like tattoos, but I think most players would appreciate the chance to ink up a bit AND have it contribute to their effectiveness in their class.

I don't think that any crafting class is likely to succeed if it's solely focused on pretty luxury items. A crafting class needs to be able to make practical items along with the pretty items.