A very interesting thread, Olympus. I often ponder over what would constitute the perfect long distance flight. For me it would have to be safe, comfortable, quiet and on time with good food and ground facilities. First-class fares are very high and I've not been impressed with some of the very expensive first/business class 'egg-boxes' that I've seen recently - very claustrophobic looking. My best first class experience (some time ago), which satisfied all of my criteria, was Alitalia BKK/SYD on a 747. It was so good I refused to sleep so as not to miss any of the pleasure of it! Another good one was a fairly recent Thai A340 economy LHR to BKK. Impeccable Service and two seats to myself, it's just a pity that LHR is still such a mess, congested and shambolic.
So back to your thread. I would probably try BKK or SiN First or Business direct from AMS leaving plenty of time at the airports (except London) for the enjoyment of their lounges. The new BKK airport I know is fascinating and AMS/SIN look good as well on YouTube. All I need now is a good deal on price and hotel, my leave pass stamped by the management, and off I go!