I fully expect that I will meet other Challengers every day of this hike. In 2008 I had a couple of days where I did not meet anyone after leaving a gathering point. The very first day after I left Dornie I did not see any other Challengers (I did meet a couple locals out for a stroll). On other days I met one or two Challengers early or late but that was it. Only a couple times did I find myself walking with groups of people for the bulk of a day. This year I suspect that will be different. I am following a pretty classic route and in some cases there really aren't that many ways to efficiently get from point A to point B. I am certainly I'll meet many Challengers at the major towns along the way and I'm looking forward to that. I have very fond memories of the evening at Kingussie and my day in Braemar. I hope I have enough time this year when in Fort Augustus to actually see Loch Ness (last time I arrived sometime after 7:00PM on a rather rainy evening and just wanted to dry off and have a nice rest). We will see what happens.
You've seen the route summary already and I thought I'd share a map with you. This route does share some of the same countryside as my 2008 trek. The hike between Fort Augustus and Kingussie is the notable repeat stretch. It's a steady climb up over the Correyairack Pass but the Old Military Road is an easy route to hike. The stretch between Garva Bridge and Kingussie is on paved single-lane road for the first several miles as your approach Monadhliath Hotel. There is also road walking beyond the hotel in the vicinity of Mains of Glentrum but it is a pretty area and you return to two-track as you walk through Phones towards Lubleathann (with a dud of a roadwork into Kingussie proper). While I've no doubt I can cover that stretch in two days I can easily see breaking it into 3 days like I did in 2008. It will depend a lot on who I meet along the way. My foul-weather alternative out of Kingussie would be a reprise of what I did in 2008. While I'd be irked if I have to go this way the hike through Glen Feshie is an enjoyable one though the last few kilometers to White Bridge on the two-track are dull and the six or so kilometers from White Bridge to Mar Lodge are hard on the feet. Finally if I take my foul-weather option out of Braemar I'll walk a few kilometers of paths I've seen before but it's hardly worth mentioning.