Indeed, i'd love to see it happen but it isn't going too, so any sort of discussion about what to do with a third is purely academic.
Agreed, which is why I didn't propose such a development, not to mention that it's financially unsustainable at least for a new development considering we have enough naval bases in the Gulf and the Al Minhad air base in the UAE and probably the Al Dhafra air base (currently have US/French aircraft based there) too if we needed it.
Again, which is why I didn't propose it (although how inflexible is an air base in the Gulf or Cyprus in reality if the goal is to protect an equally static asset such as the Suez canal, the Red Sea and the Gulf of Aden?) . Personally I'd say a UK manned RFTG occasionally deployed to the region - either in response to increased tension or in conjunction with USN operations - is a smarter presence than building and maintaining a third carrier + escorts/assets with a multinational crew and air crew.
Cheaper how? How the hell out building a third carrier, maintaining said aircraft carrier and associated escorts and support assets and training an international crew and aircrew be "cheap"? Or are the suggested countries involved willing to pay for their crew to be trained? Sounds like billions of pounds poured down the drain for a capability which would have a debatable increase in what we currently have, all this based on the assumption that nations like Singapore, NZ and Aus would think this capability so important to their own national security they would pay their crew for the service AND be willing to lose X amount of their crew for the period.
I don't like it one bit, I don't think it has much to offer which currently isn't at least on the cards to be done in the near future and seems like a hideous drain on tight funds which could be better spend elsewhere.