You could try directly south if you preferred – the Yorkshire Dales (classic Heriot country) and Peak District of Derbyshire are just about in range over 4 or 5 days.
If you have the time to get away for 6, 7 or more days an adventure up into the Highlands, the West Coast and Hebrides are all very achievable (and highly recommended). And what an adventure that would be, you, the bus and Europe’s last great wilderness, quiet roads, few people and THAT scenery. For a trip like that we’d be very pleased to help out with specific advice and additional equipment (one small item of equipment we know about has protected the sanity of many an adventurer to the Highlands!!)
A good idea when away touring is to organise a mixture of ‘wild’ nights and campsite stays. In this way you can gain the most benefit from your time away. In Scotland you are generally permitted to camp wild on public land (unless specifically forbidden under bye law) provided you act and behave in a responsible and law abiding way. A strategy of mixing wild camping with site stays means you can gain the full experience of wild Scotland and still benefit from campsite facilities.
Whether you’re just away for a short break of 3 days or a longer trip of a week or more it’s important to try and get the most from your precious time, less can be more and it’s important not to try to bite off huge distances and in fact we limit the mileage to 150 miles per day – quite frankly that’s plenty at an average speed of 50 or less!