Boffin, I cannot fault your analysis; but I don't think that your conclusion is watertight.
Whilst I recognise that the US approach insists on a little bit of good ole USA ready to respond; I just done think we have the luxury or money to attempt a forward deployed posture. In any event in many cases the US CVBG assets may not be the first to respond. ISTAR will come from elsewhere and strike assets may be back in CONUS. Moreover, even the USN will admit that they are heavily reliant on land based air to support.
So a UK forward QEC posture is going to cost a lot - far more than the cost of the units themselves. That coupled with the challenge of both maintaining ship currency and airborne competencies will not survive contact once the facts become clear... IMHO.