Shaw Farmer,What you say is interesting,particularly if you come from a JAZZ BACKGROUND.
Sometimes the approach is different in traditional music,hence the fondness for open tunings,and the avoidance to some extent of major and minor thirds[Martin Carthy is a good example],these modal chords still often have added 7,9, 11,etc,but are much more ambiguous.
some guitarists have followed an alternative route[WillieJohnson] which is more jazz influenced,neither [imo]is right or wrong.