Thanks to all for the suggestions - keep them coming (there are probably more than enough already to keep me going but people's views are interesting. I'm sure my son will have some too having been there for a few months but he probably won't have the same music interests as me :)

Joe (thank you for the detailed input - very useful)- we haven't sorted out where to stay yet. We were thinking of playing it by ear and deciding as we go. The only limit I guess is getting back. But it will probably be a one off trip so there is a temptation to see what we can while we are there.
The weather is probably the least important thing - I like Scotland and you only like Scotland if you like weather (on the basis that it will be different in an hour or two's time). Sun is not that important and beaches and sunbathing defintiely aren't

Do they have singaroundy/session things there? When we went to the East Coast we went to a bar in Maine (I think) which was very like UK stuff and could have had a sing with others. It's not a crucial thing but just a thought. We went to Crete recently and found a nice bar to share music with people so it' nice to know if these exist!

The thing that my son has most noticed is the homeless which he was astonished about.