The Rob Roy Way Runs 79 miles from Drymen to Pitlochry or Pitlochry to Drymen Scotland.  It has a few deviations but the main route is 79 miles.  It includes passing through historic towns including Killin, Aberfeldy and Start or Finish in the Historic Village of Pitlochry.  I'm planning an FKT on this Route on August 13/14th and would love it it was included as a formal official route before I attempt it.  

Several websites have detailed information

From Official Website: