CX really have no other option in this case.
The aircraft already has a long turn time in ZRH (6 hours) in order to get into HKG early in the morning. This opens up connections throughout Asia and to Australia.
I can also tell you that it is a lot nicer having the Europe - HKG sector as a daytime flight than the HKG - Europe flight as a day time, as the latter is about 2.5 hours longer flight time.
Well, different people, different tastes about schedules I guess.
Still wonders me, why wouldn't they do an afternoon departure in HKG, arrival in early evening (departure 1pm, arrival 7-8pm or so), then return flight as a night service..
Or would there be no connections in HKG at 4pm, when the flight (like LX) would suppose to land?? I know that connections have to be taken in mind, but LX is happily feeding SQ's flights in SIN with their 4-5pm arrival in SIN.. is there such a difference to CX?