Well, it would be a great feature to add, but we do have a few modifications and whatnot already with this feature (for one, FeralHeart HD). Plus, it is a bit hard to put newer additions to the game without the proper codes, so I don't think that these new markings would be implemented in the game any time soon.
Again, it would be pretty amazing for new markings that everyone could see without having to download more things onto their computer.
-Wolfie
(P.S.: FeralHeart HD is an amazing mod to have, I would recommend it!)