I used to transit through MAN. Air Canada used to fly there, with onward connections to Europe. I used to quite like that route.

Now that carriers have cut their routes outside of London, it doesn't work especially well, and I almost always need to transit through LHR now, which is a pain. On the last shuttle I took, I think virtually every passenger had an onward connection, which is logical, as it is quicker to get the train from Manchester to central London than it is to fly. In fact, if I am going to anywhere north of London, I get the tube and train, as it is quicker than connecting through to do a flight there.

Even if you did not have as frequent flights, I know a lot of people who would prefer to avoid London.