Good question!
Planning 10 days for the trip with probably 6/7 days in the UK. We're looking for a good mix of nice roads, sights and attractions. I'm thinking of a day at Alton Towers for example as most of them would enjoy it and the roads around there aren't bad. They also want to visit Loch Ness and a whiskey brewery (is that what they're called?) or two.
They're all Swiss so not easy to impress with roads, but I want to show them that we hold our own here. The idea of riding through forests is particularly different for them as they're used to lakes and mountains.