Selection Refinements
Selecting two different family types currently greys out [Select All Visible in View / In Project]. There is no useful reason for this -- it should allow multiple families or types to be filtered and all instances then selected; at the same time, there is a bug in Revit that doesn't allow Select All for a given Line Type, this should be enabled.
Secondly, the Dimension Properties, Area and Volume are hidden -- this should remain visible and show a total for the selected elements.