I will try to answer as best I can.
Holding traffic is not something we are doing too often, we are just not quite busy enough to justify that. With the traffic coming in through 5 different gates, it is also difficult to regulate the traffic via the holds, and we might end up wasting space on final if we don't bring the traffic in early enough (it is a long way from the holds to final). Also just having 2 holds and 5 gates makes it difficult, if you come in via TANGA or ATUDO there are no holds to put you in, even via NOBTO you have to be taken out of the way to get to KIXID hold.
Also, as soon as we do activate the holds, our telephone lines are glowing red with ops departments demanding to know why we are delaying their traffic....
Do however expect that the holds will be used more soon as traffic levels are soon to increase again. Until then, for informal planning, we have a landing interval of about 2 minutes, and add 2 minutes for each departure as well. So if you are told you are number 11, you can expect to be on the ground in 22 minutes at the earliest, but probably in 26-30 minutes if we have a couple of departures as well
As for the descend down to 2000 feet on downwind it is quite simple - we need to get you out of the way from the guy behind you. Our airspace is very limited with military airspace to our south, so if you are on the 2C arrivals for 31L/R we cannot take you further south on downwind, meaning that if the plane behind you are at same level as you are I cannot turn you base/final untll you are 1000 feet below his level as the inbound turn from base to final is normally too close to the downwind track.
And it might be that for your flight we are wasting a couple of 100 kgs of fuel by doing that, but if you are micromanaging your own flight and fuel, refusing to descend (or setting a 200 feet
pr minute ROD) we might have to keep you on downwind for a minute longer, and therefore on final for a minute longer too, meaning that every single flight behind you are also delayed by 2 minutes each... so even if you saved yourself 200 kg of fuel, you have wasted 20 minutes of fuel for the company if you have a sequence of 10 aircrafts behind you
And as a note, please remember that speed control are also ATC clearances, we do issue them for a reason (to separate you from the other aircrafts), so please follow them, and let us know if you are unable/unwilling to comply. there is a GCAA requirement that we should file a ROSI for anyone not complying with speeds, and we will be starting to do that very soon.
Also, please help out by getting the aircraft off the runway as soon as possible after landing, so we can push the spacing on final more, and get more guys off in between. It is interesting to see that the biggest local operator often is not able to vacate via E8 on 31L, whereas their brother from up the road always vacates via E12 when they are visiting. I know that brake pads costs money, but so does delaying arrivals because we need extra spacing due to long occupancy time...