EGLD.
I quite understand the locals reluctance to accept another runway and it is entirely reasonable to suggest that the load be spread around but that still leaves the unanswered question of what is going to be done about the overbearing of traffic which ALREADY exists at LHR? It is a 2 runway airport handling 3 runway traffic and that cannot be left unaddressed.
Jumpseater.
True enough, there is plenty of airspce north and east of STN, so it will be fine when they are on westerlies. What about easterlies? If you are an approach ATCO, how would you feel about vectoring into a short (12nm) cul-de-sac surrounded by other traffic, with a single level and no way out when a thunderstrorm goes through? No room to orbit.
PB. Yep, you read correctly. The C17 will do 15,000fpm max rate of descent with the boards out and the engines in reverse.
Point 4