I completely agree with you, and I suspect that’s the reason behind SOU’s masterplan and proposed runway extension. The market they currently cater for is slowly declining and so they need to be able to lift themselves up to the next level of airline (European locos flying jets) to have any chance of staying competitive.
It seems like it’s either go big or go home. Happily, the indications at the moment are that they’ve chosen to go big. How soon that happens is still up for debate.