Aye we went the second week of Sept '22, after the English schools had gone back. Roads were a lot quieter, midges few and far between, weather still bloody lovely, but windy.
As others have said the West Coast is stunning, we did the North Coast 500 last year. I've travelled to far flung places across the world, but the NC500 is up there in my top 3 holidays, it blew us away.
Again as others have said if you can see your way to go further north you won't regret it...