Sounds like a great idea, but i will never forget my first visit to the NE Highlands, last October.
I just could not get my mind around the extreme isolation and remoteness of the land way beyond Inverness, i had never seen such isolation, let alone single track roads for mile after mile, into desolation.
I stayed in Dornoch, and traversed the wilds towards the Kyle of Tounge and back via Ullapool.
Mapping every path in that area, would be virtually impossible, and i sure take my hats off to the OS staff who catalogued all the high mountains in that incredibly remote part of the Uk.
I recon the current OS mapping of the Highlands will be the best we are likely to see, as the task of mapping every path, is virtually impossible, or a very costly and time consuming exercise.
Scotland to the South of Inverness, is very straight forward, as this is where the major population of the country resides, but the real remote areas near Benn Hope, that's a huge ask from the OS lads.