For those short of time for a long cycle tour, would you be interested in joining 2 cycling buddies, Jon and Megan, to cycle the 185 mile Hebridean Way that runs the length of the Outer Hebrides. Take a look at Mark Beaumont's cycle of it if wondering what its like. https://www.calmac.co.uk/article/4556/Hebridean-Way-Cycle-Challenge.
Plan to take 4 days going from southern tip to northern and camping along the way. The route isn't especially hilly but can be quite windy. But the stunning scenery and wildlife and the remote way of life should make for a great experience.
The plan is still a work in progress, but as an outline. A day for everyone to get to Oban and plan we all stay overnight there. Next day take the ferry to Castlebay on south Uist, takes about 5 hours, and then cycle down to Vatersay ( about 10 miles) where Hebridean way starts. Roughly cycle 50 miles a day , planning to stay in campsites with hot showers, but can always wild camp in Scotland if ferry crossings cancelled. If weather turns bad, there are bothies and the hostels should have space this time of year. Once reach end of route, Butt of Lewis, cycle to Stornaway to get ferry back to mainland at Ullapool ( 2 hour crossing). From there its 50 miles to Inverness and for those who don't fancy cycling it, there are companies that will take you and your bike.