I know what you mean about LCY - just a pleasure to use. It's a pain if you have to head over to say, Richmond or Ruislip, but for the centre or east of London, it's a dream. I choose it every time I go to London (which is always short-haul).
I also choose to travel Porter whenever it's possible when I'm going to or leaving Toronto - Toronto City airport is incrediby central (less than 1km from the central business district?), with added bonus 2 minute ferry ride from the city to the dinky little island.
Long haul from Europe into South-East Asia or the South Pacific/Australia from Europe, there is almost always a plane change.
Choosing between Dubai, HK, KL, Bangkok or Singapore is a no-brainer: Changi is hands-down winner. Long waits are handily dealt with by the free city tour or the short MRT trip into town to pop into Little India or Chinatown or the malls, or the beach or ... Airport facilities are generally awesome, especially the (groundside) basement Hawker food hall in the fourth sub-basement of Terminal 3. I love the rooftop pool on Terminal 1. And SQ is a good reason to choose Changi all on its own.
So yeah, I choose airports and airlines based on facilities and pleasure of use. For long-haul the differences can be a matter of only a couple of Euros, but the difference in the experience, the amount of saved time etc is significant.
Decent TGV services mean than I haven't had to use the god-awful CDG place for many years. I hope the same sorts of services will be implemented in the UK at some point.