Even though it is not signposted for crew use, in Brisbane I have been told by an AQIS inspector that the express lane IS for crew use as well as those pax wih an express card. This takes you to the head of the queue, where you are directed out (if green stamped) or to the xray or inspection tables as appropriate. Some years ago I asked the government powers that be in BNE if a crew lane could be established for the purpose that the express lane is now, it seems, available for, but after several pages of waffle was informed that to do so would require 'a major policy change'!
The responder seemed to think that my suggestion was that crew bypass all quarantine checks. When I wrote back to clarify my suggestion I received no reply.
I frequently operate into and out of BNE, and have had very few problems with either the passport control people or AQIS, and 9 times out of 10, have had the green stamp within 5 yards of exiting the passport check.
As to crew bags of first, last or in the middle - that surely is an airline broblem - not the airport authority.
What the airport may be responsible for is the last minute - one bag not screened, we need it back before you can go - and that inevitably happens at about the time the last door is closed.