Nympsfield would have been interesting if you are used to runways. It's a nice, big expanse of grass but distinctly up and downy! A/c in the first and sceond dips aren't visible from the launchpoint, to give you some idea.
Planning permission is often the big issue - my airfield (Ridgewell) is no power other than tugging, and a former club was restricted to about a dozen non-tugging movements each year.