We went through Glencoe in early September on the way to Contin for a couple of nights before going over to the Hebrides on Ullaway to Stornoway ferry. We've been through a few times now but always been a good route with, hopefully, opportunities to pass slow vehicles. This year we did the return run as well rather than the A9/Perth route. The roadside carparks were jam packed and one "logging" lorry pulled over to allow traffic to pass. The Plus Four was excellent to drive with comfort and performance when needed.
The Inverness to Ullapool road is another good drive. We did Applecross pass downwards having gone up last year.
Going in April and September means less traffic and midges!
Lewis, Harris and Uist were good for scenic drives, no time to go to Barra though. Cafes in the day and hotel for evening meals, fuel stops ok as miles driven not great. The return to the ferry on Uist was at daybreak and the deer/stags were out in force.
Next year? Can't do September but April undecided so far, another continental trip being considered.