Since you have some extra time built into the schedule, how about going a bit south of DC? There's a Hyatt Place in Charlottesville, VA that from Indy will take you across the Appalachians through some really pretty country. From there, Bethlehem PA would be a day's drive, which would easily put you into Newport on the third day. Both the Charlottesville and Bethlehem properties would be Hyatt Places.