-
I'd focus on terrain profile rather than milage. The East coast is much less hillier in general and distance will depend more on where you want to camp/stop. I.e there's a gloriously tacky seafood place in Helmsdale called La Mirage that's worth poking your nose into for dinner, and a good cafe for breakie if you choose and shop to restock. Not many towns on that stretch are similar!
Cairngorms are also pretty much fine as the roads skirt them, Eastwards you'll aim towards Braemar and Glen Shee which is lumpy but not impossible, and you can route around the Lecht which is undeniably a fucker but less so than coming over it from the South.
When I've gone touring with GF I've been terribly negligent at looking at elevation and ended up feeling very guilty by driving her along some pretty hard days-she did enjoy and get a feeling of satisfaction from it but I just became aware that the distance was a totally daft way of planning.
What's a realistic daily mileage for a first tour?
Leaving for Scotland on Saturday and given ourselves 2 weeks for jog-Edinburgh. Works out at around 25mi/day average. Both competent riders but first properly loaded trip, plus the Cairngorms are in the way.