See attachment
I think it would be a much more userfriendly interface, if itemlists under groups were not shown in the page structure, as the structure can get quite big and confusing. Also it would be very nice, if there were different options of sorting. And best of all, if there were options of setting a default sorting in the listview.
Let me know if you want me to ellaborate. This is not the same as the current item lists, as I still want them to behave as "pages" with separate URL´s
Hope this makes sense?
Umbraco has done this in Umbraco 7, but not with the sorting options as far as I know.