The problem is that with digibox packaging often there will be an image of the front cover (as type Front) along with an image of the whole digibox folded open showing the front and back covers along with the spine (and marked as types Front, Back and Spine). Are you suggesting that these images be removed, or not marked as being Front?
In the example that I was using for testing, there are 4 CDs in a box set. Each CD is in a jewel box case and each has a different front cover. Then the cover on the box set is different again. Simply removing images doesn’t seem to be an appropriate solution in that case.
Let’s face it, with the diversity in packaging there really isn’t a good “one size fits all” rule to follow. Or if there is, I have yet to find it.