I agree that Vancouver is a pleasant airport to use but there will be no metro rail link until the Winter Olympics, the "Airporter" coach to/from downtown is very expensive and the local Translink bus only serves the domestic terminal (with passengers who use it having to change to get to/from downtown).
I think that compared with Heathrow, Vancouver simply has the capacity to cope with the numbers using it. For example, I've never had to queue when using the FastTrack security line.
(During the recent snow, though, there was absolute mayhem when it came to locating "lost" luggage.)