or pay the costs for a decent civilian flying school
Nooooooooo!
I did a flying scholarship at one of the best civvy flight schools, and they taught me how to fly safely and well.
Then I joined a UAS and they started from scratch..., and taught me how to
master the aircraft, which is completely different. My UAS instructors had flown Spitfire, Meteor, Hunter, Lightnings (2 of them), Canberra, Hercules, Nimrod, Shackleton, Liberator; and they taught me stuff both inside and outside the cockpit that proved profoundly useful later.
Gliders with RAF Instructors would be a much better bet.