San Diego,
Yeovilton's has certainly gone but I may be wrong about Wittering, I've not been there for a few years. Unfortunately I'm not based in that part of the Country these days.
Something Engines hasn't mentioned in his excellent posts is that because of the UKs involvement in F-35B the flight control software has always been written with a ski-jump take-off in mind. It is not something to be newly coded and loaded into the aircraft.
Geometry is no different for the new carriers in that a 12 degree ramp was fitted to CVS and is fitted to Queen Elizabeth. The difference is that the QE ski jump is longer and less abrupt.
Not sure about putting one at Marham. I think some people are still struggling to think of 617 Sqn having to go to sea
