I am mystified why there is concern over number of routes from one airport, and pure size, when if one looks at London as the whole market of the four major airports, plus London City, the London area is probably serving far more destinations than the competitors in Europe.
Political foresight be damned - we know there is none of that - all we need is good old-fashioned competition (breaking BAA's ownership of 3/5 London airports), and sensible, quick planning laws allowing quicker development. In the meantime, we can only hope that BAA goes bust to save us future aggravation...
Heathrow can have their third runway and sixth terminal, while other operators may see better solutions that attract carriers to other locations: no-one needs to collate them in one airport: in the era of more open skies, fewer people will bother connecting with more direct flights.
"Central planning" and "big ideas" are a little too much like communism for my liking...