All CAT 1 & 2 holds are co-located except on K at HKG. On 07R you see them taxi down H and then hold on J1 abeam J, way short of the holding point. Then just release the brakes with no additional thrust going uphill slowly moving forward onto the runway. Meanwhile the preceding aircraft has already gone through 2000' and is talking to departures before they have completed lining up.
What I also experience is aircraft not following ATC speeds (assigned the same speed and catching them, or ATC asks and they say 148 kts and they get asked to maintain 160 to 4 nm), and then using A8/A9 in an A320 or 737 as they are parking at the satellite terminal. Nowhere near as many A320s/737s seem to need A5/A4 when landing on 25R.
The wasted time with poor speed control, and unacceptable runway occupancy times is costing a number of movements an hour (and go-arounds). Should be able to get arrivals in with 3-4 miles between aircraft like other busy airports, and departures more frequently.
There is also free slots late at night, but they are useless when the public transport to and from the airport goes on the restricted nighttime schedule. I think the AEL and hotel shuttles should run at least once every half hour through the night. Taxis rob visitors blind on the longer trips to the Airport, Kowloon and the Island.