A smooth flight that brings you to your destination on-time, without hassle, and with you leaving the airport happy.
A posh plane may help, but it is the friendly and efficient service that really matters the most.
I would say the ideal would be the CO HKG ground staff + CX / SQ cabin crew + JAL meals + EK / QR(int'l fleet) planes. Now... that would be something to look forward to 
You forgot to mention EK IFE
