As Lap Sap says above, be aware that renting accommodation in Hong Kong is on a completely different scale to many other countries i.e. It is very expensive and you will be in a small flat, possibly in a high rise apartment block. To give you some idea of the likely housing costs, 20 years ago the accommodation allowance was £37,000 per annum.
The salary on the Civil Service Master Pay Scale is virtually the same as it was 20 years ago i.e. £107,000, so don't expect an annual increase, however there was a 25% gratuity plus air fares, medical and education expenses for children. So, the total package 20 years ago was close to £180,000. Tax is 15%, so a lot lower than many countries.
If I was contemplating a move back to HK, which I'm not, I would be looking for a package north of £200,000.
I've yet to see any adverts for HK, but I assume that the package that will be offered would be of this order.
The work is not for the faint-hearted. Traffic levels are almost on a par with Heathrow but with airspace constraints that severely limit vectoring in the APP/DEP environment.
On the en-route side, again very busy and a challenging environment, 24 hours a day, and growing at an alarming pace.
Bear all this in mind if you are considering applying to HK.
However, the work, although challenging, can be extremely satisfying and outside of work HK certainly has a lifestyle that is out of the ordinary.
I look forward to seeing an advert.