Whether you like it or not, the tide of history is moving from smaller to larger groups.
Once it was small groups of humans led a hunter gatherer life. Then the groups got bigger, people settled and the villages turned into towns and so on.
We have seen that progress. Most city states are now subsumed into nation states and the trend over the last 50 years has been for voluntary association of nations into larger units. The UK is in several of these units including NATO and the EU. There will always have been people harping back to the "good old days" and we certainly have some of those. Scotland has escaped too much attention from UKIP and other xenophobes because they are often seen as specifically southern English. When we want ignorant statements about people on the other side of a line on a map,or speak differently, we have our own.
I really could not care about how the UK was not created well. It can work well nowadays. 1745 was a long time ago. It is good for tourism and film makers but I do not work in either of those industries. Like many people, I benefit from being in the EU. It means that, as part of the United Kingdom, I am part of an economic grouping that is bigger than North America. Despite what the SNP tells us, if Scotland leaves the UK, it leaves every alliance the it is in. It will be able to apply for entry but this is not a fast process and meantime, we are outside.
The UK is not perfect but neither is my car. I won't make my car work better by sawing bits off. We need to fix things, not land the entire population of England perpetually under Conservative government because we have taken our MPs out of parliament.
Lets move the capital of the UK to somewhere near the middle of this island and away from the cleared swamp that is a drain on the whole country. How about York?