They are not that hard to add in, more of a hassle is all. If you have ideas for tattoos, I would suggest you speak with the Clan staff over the area of the tattoo vendor. Allanak for example would be under the Southern Team, Red Storm would be under the Indie team. This is entirely at the discretion of the team and if they have the time to do any of this of course. At the very least, put in a Question request to see if they are open for the idea before going all out writing new tattoos up.
I personally am open for ideas as long as they fit the theme of the particular place they are, but I make no promises on time line to get them added or if they will even be accepted. I will actually be placing an announcement here in the next couple weeks on an area of the game I'm working on and want feedback on, so that may also include updating tattoos.