We can easily create custom post types but those post types using only article focused panels similar to "posts" or "pages". I believe we need media focused post types that similar to "attachment" type. "Attachment" post type have special panels that allows image editing, batch upload etc. This is really a necessary usage for "special" medias like portfolio photos. In my research, i see we cant use "attachment" post type's custom panels in custom post types at the moment. I think it wont be hard to let developers use those panels right?