As for Scotland joining the EU. Even if Scotland does become independent (it won't), the EU wouldn't let an independent Scotland in.
> In order to join the EU you've got to have a budget deficit of 3% of GDP or less or be obviously (which allows for some fudging) moving in that direction. And Scotland, now that oil has plummeted, simply is not there. It's difficult, given the intertwining of British and Scottish accounts to get it exactly right but reasonable estimates have the Scottish alone budget deficit at 8 to 10% of GDP.
https://www.forbes.com/sites/timworstall/2016/06/26/the-prob...
Scotland cannot sustain itself at all on its own. The SNP run Scotland poorly (and it is in their interest to do so) so it would have to go under massive austerity the moment they go independent.