Bagso, I am absolutely aware of what you have stated. I went to Uni here and the course was something that often focused on several of the areas you highlight. However, Manchester United, Selfridges, MEN Arena and a tall hotel cum appartment block does not make a City a powerhouse. They all contribute to a vibrant, exciting City but none of them particularly make Manchester outstanding.
Manchester is a great City....I love this place but I am not going to pretend that it is a powerhouse when it is not. With the birth of the industrial revolution and the cotton industry peak, Manchester was indeed a great powerhouse but has since lost the status that very few Cities enjoy. London, for example, is a powerhouse.....it has probably the worlds largest Financial centre. I wouldn't class Barcelona, San Francisco nor Rome as powerhouses either because there are actually so few.
MAN as an airport fully deserves and is very capable of sustaining the routes and carriers which operates there but at the same time has attracted a portfolio of carriers and routes that many similar sized Cities, including many Capital cities, do not enjoy.