Flying - too much hassle
Flying within mainland UK makes little sense really. The obsession with security, baggage restrictions (what you can carry - again security realted), check-in queues, security queues, boarding queues, waits at baggage carousels - thats before the car parking costs.
No, there is a better way - the train, if you can afford it, and even driving on our crowded roads is preferable.
There would have to be a compelling reason why I would fly domestically for pleasure - business possibly though, but only if time really is an imperative, over a long distance.