Britannia here we come :-) Advice welcome!

[JustMe]

Cheers everyone,

having travelled through Eastern Europe last year, we have on rather short notice kicked the idea to ride to Turkey because it will be too hot for the kids riding pillion (we had 40 degrees in Romania last year already). So it´s Britannia this year, three weeks from around 15 July onwards.
I´ve been repeatedly travelling to the UK, hiking in Scotland in 1983, having studied a term at Guildford University in 1989 and now having business partners in London, Newcastle and Southampton. I´m comfy with driving on the "wrong" side, and Missus (with her Transalp) has decided to be tough as nails and try it, too. The boys are 14 and 15.

The ultimate destination are the Scottish Highlands, however, we do not intend to enter the iron butt association anytime soon and want to enjoy the travel, relax in between, hopefully spend some time at the coast and do not more than about 250km / day. We think about making landfall somewhere in the southeast, e.g. by Eurotunnel or ferry, travel up rather on the western coast (never been there),
However, I do not want to spend much time crossing bigger cities with much traffic or travelling on the Motorway, but rather take the countryside roads looking for Miss Marple and Lord Peter, so if anyone of you could give us some hints on where to go (nice landscapes, scenic coastal tours, moors....) what not to miss (museums, exhibitions, architecture, bike meetings, whatever) and where to stay (campsites, wild camping, B&B, national park campgrounds) we´ll be utterly grateful, thank you very much.
Best regards
Chris