Actually St.Mawgan was very well-equipped. Apart from the huge runway and a strategic position (the nearest major airfield of comparable size is now Brize), the base boasted a very healthy collection of dispersals (including four which were widened for QRA V-Bombers), a standard apron plus a huge second apron, a monstrous Nimrod (formerly Shackleton) servicing hangar, a HAS complex, a nuclear weapons compound, an entire (disused) secondary airfield attached to it, an airport, and proximity to reserved airspace. At one stage it hosted two Nimrod units and a Canberra squadron plus numerous deployments and exercises. But it was abandoned. So on that basis, I don't think any air base could be regarded as "special case" in some way.
Clearly, the current appetite for cuts is based purely on cost and has little or nothing to do with operational needs or common sense. This is why Kinloss will doubtless be a victim. Likewise, it seems quite likely that the Harriers and Wittering will also get the chop. I don't think the process will end until the Navy is a helicopter-only force and the RAF's combat aircraft fleet comprises exclusively of Typhoons. I really do think that this will be the ultimate result of this process.