I've been lurking for a while, as a non-Scot with a British passport, resident in England (so no vote). Although born in the UK I was brought up in New Zealand, with an English and a Kiwi parent, on the Kiwi side I have scots, irish, welsh and english ancestry.
It strikes me that I have more of a "british heritage"/ see myself as descended from British stock (rather than english v scots v welsh etc) view than many of the people who were brought up in a particular part of the uk. In the same way that expat Italian and Greek communities in Australia are arguably more "italian" or "greek" than the younger generation in either of Italy or Greece.
Re financial services, I suspect it's not just HQs that are going to be the issue. I haven't done the analysis but my gut feel is that outsourcing service provision to a non-EU group subsidiary, particularly where regulated services are involved (custody, fund valuation etc) may also throw up some issues.
Ultimately I get that it's up to the people of Scotland. I originally really wanted Scotland to stay but having seen some of the "Yes" vitriol on TV I now feel quite neutral about it, and I know a number of people here in the dreaded south east who are, as a result, hoping Scotland will vote Yes. DS (age 9) who has been watching the news suggested that they record people's votes and only continue British citizenship for those who vote no. As he sees it - having watched the news and not been coached by me- "if they hate us that much, then let them have their own country and let's build up Hadrian's Wall". Made me quite sad.