I come from Stirling and now live in Falkirk. Both fantastic places and extremely beautiful! They are both within 30mins from Glasgow and Edinburgh, but have MUCH more affordable housing. Stirling is a University town (I studied there) so the whole town (now has city status!) is very multicultural as lecturers from all over the world live and work there.
My DH is about to start his training as a Supermarket Manager with Tesco. Which firm does your DH work for? Stirling and Falkirk have numerous Tescos as well as Sainsbury's, Asda, Morrisons, Somerfield... all of them really!
So don't limit yourself to the 'big cities'. You can have the beautiful mountain setting and historical castles without the small-minded country attitude that is all to often present.
As for the Scottish-English thing? I am Scottish and my DH is a Scouser. He has had no problems at all with living in Scotland (been here 5yrs now) and now won't leave here, even though I offered to move nearer his family!
In the Stirling and Falkirk area try:
Bridge of Allan
Causewayhead
Stirling Town Centre
Dunblane
Larbert
Stenhousemuir
Polmont
Brightons
Falkirk Town Centre
These are a few of the best areas.
Incidentally, one of my friends graduated from Stirling University with a degree in Religious Studies and now teaches RE.