A Dewey Metadata field is an absolute requirement. I'm surprised it has not been added yet this far in development. It would be most useful to see this editable field sortable in the list view. Perhaps a collapsible tree with subs, like when categories and sub-categories are created, would be most appropriate.
This, for me, is the only feature missing from this most excellent piece of work. Perhaps you feel the same.
Please speak up if you would like to see this type of metadata imported from the web.
Vancouver, Canada