Completely ruled out the other three then? In terms of campuses, Glasgow and Stirling are probably the most obvious- Edinburgh and to an extent Strathclyde and Dundee are more spread out. In terms of course makeup, while I don't want to overdo it, Glasgow has the most flexibility by a long away- for single honours you can effectively experiment with two other subjects and drop and pick up modules as you please.
Glasgow is as close to a self contained campus uni as you will get within a major urban area in Scotland- Edinburgh and Dundee are more spread around, where as Aberdeen is a little further from the action. As a result, the social scene is usually excellent- if you live there you can easily get involved in the things that are happening. I've been a freshers helper three times, and the students seem to get out what they put in- if you don't go/hold back, then you won't have half the fun you do with getting involved. If you can afford to stay on campus or its not too impractical, I'd certainly recommend it.
I wont go into too much detail about the other three unis you've ruled out, but I have nothing bad to say about Stirling. Its a different atmosphere to Glasgow, but I have friends there who love it. Its sports facilities put the rest of Scotland to shame (and Glasgow's are far from shabby- they just spent millions on them), as they have olympic training things there, they are really top notch. I have a friend who teaches in the Business School at Glasgow whos formerly been part of the British Marathon Team and has been educated at Edinburgh and Loughborough, and he'll vouch for that statement. Its a bit of a campus bubble though, and the town only has a population of 50,000, so in four years time you might be a little bit bored- the dropout rate after 1st/second year is relatively high as a result. Perhaps wrongly, it doesn't have quite the stellar rep that the big three Scottish Unis have- but it deserves to be more widely recognised, and perhaps in later years it will be.