I think that since here are a variety of different dead ghost shells that you pick up in the game that you should be able to choose from one in that particular Grimoire Group once you have completed the Grimoire section (Example linked: ALLIES // LEGENDS & MYSTERIES). But if you find them all within the base game have or a particular DLC then a another option should be available. Something like Gold for the Base Game, Spiked Ghost (Like Glass Minuet turned in to Bane of the Gods) for the Dark Below and Bluish Glow (Like on the Hildian Seeker) for the House of Wolves DLC. I think that it is really, I guess, silly that the only other ghost shell currently in the game (Unless you hacked your profile - Intrusion Shell) you can acquire is from buying a certain addition of the game when the physical ghost model is the exactly the same and only the graphic textures/colors are different. There should be just as many options for the ghost as their are for ships. Or hell, at least have the ghost change color based on the shader that a guardian is wearing or allow the player to apply an acquired shader to the ghost itself. Then additionally give the options I suggested at the top for game "completionists", like me, who like explore. I think this would also bring another nice conversation starter when people inspect your character or see your ghost opening a door.