H_H I am slightly disappointed, but not suprised that you found some RAF Admin officers who didn't rate their careers. Over my time in the RAF I've come across many people from many branches, aircrew included, who didn't particularly enjoy what they were doing or felt they were not satisfied in the RAF.
My point is don't let yourself be put off by the moans of some people. My experiences, as an Admin officer have been fantastic, and I continue to enjoy my postings. I have served in 7 countires away from mainland UK; some great beer drinking places and some a little hotter and not quite as social. I have had a good range of jobs, serving on flying stns and in HQs/MOD, and worked closely with the RN and Army. I would certainly say that I am not unique in my Admin career profile to date.
My advice would be to have a close look at all the branches that the RAF offer and see what you think you are best suited to. In my experience any air force job is what you make of it and the great people you meet along the way.
Good luck!