1. HK runs single runway ops overnight into the early morning. You can expect to land on 07R on certain days.
2. If the weather is good, ATC will not protect the ILS sensitive areas.
3. There is no need to fly an ILS in good weather, other approaches are available.
4. The GS fluctuations are reported via a Digital ATIS....you can get this outside of VHF coverage unlike other airports...so you can spend the 2-15hrs of your flight inbound coming up with a plan...there is no surprise here.
5. If you still choose to fly an ILS, you have accepted the risk, best have a plan if you encounter an aircraft upset event. Your decision.
6. If anything needs fixing in HK, it is the extremely inefficient airspace....particularly for arrivals from the north....and there is a 3rd runway under construction.
7. GS fluctuations during single runways ops in the late night period in VMC is a minor issue easily managed by experienced crew....ie don't fly the ILS!