Democracy and responsibility
There are ten times as many folk in England. They often vote in a way we do not support. We end up getting what they chose by virtue of nothing more than mathematics. This democratic deficit leads to Scotland being regionalized as a people and an economy, to a devaluing of ourselves, and social inequality at the 4th worst in Europe. This is corrosive to our identity and culture. Scotland needs true democracy and the responsibility that comes with it, and that's just not possible in the U.K.