Make the gear appearance an unlockable feature that players always have access to on that character, regardless of whether it remains in their inventory or not. (will still require scrolls to utilize)
Benefit:
Players - bag space saved and more content to chase.
Warmane - more $$ due to new transmogging system allowing players to pursue 100% item appearance collecting.
would be nice, i'm also hoping in the future we will also be able to get non-drop / npc items for transmog, like the blue t10 warrior set, frostmourne like on blackrock etc