WW I agree!

It makes sense that the images should follow some order to make the database look uniformal.

To me it should be:

Slip case front then back (if it exists)
Booklet front
Booklet internal pages (if scanned)
Booklet back
Inside tray (if it is printed)
Outside tray (the back of the cd) (with the spines)
Disc
Any inserts
Any case stickers