Perth is easily the worst airport in Australia. In my opinion the congestion problem often has little to do with runways and a lot more to do with apron/taxiway/bay congestion.
Nautilus, the runway election in PER is often quite sub-standard. As you know, the wind figures you quote are aerodrome winds. Very often I've had very strong tailwinds on final, especially on 21 at night, and this has been reported by aircraft. Yet because the wind on the ground was "only 5 kts" tailwind no runway change was made. A 5 kts downwind is no big deal, but in a Heavy a 30 knot shear to a 5 kt DW is! Often the downwind is above the 250 ft anemometer so, unless we happen to hear preceding traffic advising, we have no idea to anticipate this and hence require the opposite runway.
It's difficult to take any ATC system seriously that follows an aircraft for 4 hours as it crosses continental Australia, then advises shortly before top of descent of a requirement to lose 10 minutes before the next waypoint
Many times I've been at a high cost index across Australia in an effort to make schedule/curfew for a return, only to be advised of a significant delay to cross BEVLY
I'm definitely not trying to have a go at any ATC people on an individual basis, I appreciate it's all according to the books, and I expect the frustrations are possibly shared. I do hope the comments on the runway selection give some food for thought however. Flying a heavy 747 or Airbus into PER can often be "sporting" to say the least (particularly the Airbus). It definitely doesn't help to discover a howling tailwind on final that was reported by preceding aircraft hence known by ATC. There are times when we wonder if the runway chosen is EVER into wind
With regards Flow into PER, well sorry but from a user perspective it's crap. I've never seen anything like it anywhere else in the world and there's nothing more to be said about that.
About crossing times. Occasionally we all screw up, for example if the winds on descent turn out to be radically different fro forecast. However if anyone finds making an ATC crossing requirement within 1 minute typically difficult to achieve, they should probably be thinking about a career move!