How about adding left, right, top, and bottom spine tags instead of a general spine tag? (Quite often boxes have different spines on the left and right, currently the system cannot tell which spine belongs on which side) Japanese Sega Saturn boxes come to my mind
Magnetic media image type for cassettes and floppy disks, instead of tagging cassettes and floppies as carts and discs?
Other as a region tag...for countries such as South Africa for example
Spine card tag for inside insert spines.
Instructions, controls, cutscene/intermission as screenshot types