You missed THE ISLE OF GRAIN where Lord Fosters proposed airport would have been situated!
Other than the transport and motorway infrastructure needed for this major project personally I think it is the best location if there was ever to be a brand new airport for London although obviously it won't see the light of day.
A lot of people get confused with the BorisAirport and the Isle of Grain project as there both the same not the artificial island as some including the media imply which would have been situated north of Margate and was discounted along time ago.
I'm now in mixed minds as to where the new runway should be situated but ideally both LGW and LHR should both be given permission to build a new runway each but I just can't get my head around all the mess that will created around the M25 and M4 if R3 is the only option, haven't we had enough of all this motorway chaos regarding Smart Motorways to end up with even more around LHR as I am a very frequent user of LHR and the M25.
LGW for me if I was asked and given just a second to think about it!