The best option, as it turned out, was regular public transport, and a meandering ride through some of Perth's lesser socioeconomic zones. I'm not phrasing that as a put-down, more a comment that people who could afford not to live under the flight path would prefer not to.
Those factors would be exacerbated by late-night departures, but you would presumably learn to sleep through it.
It's a couple of blocks between Citiplace and the bus stops. We set off through the gathering dark, arriving just after one bus had departed since it seemed like a good half-hour before the next one came. The trip itself was unremarkable, though had we been travelling another day at another time things may have been different.
Seven-thirty on a Saturday night is not, as you may suspect, prime people moving time.
That still put us into Departures with two hours till check-in time, so the scribbling resumed, broken by an investigation into the coffee shop possibilities. That check revealed that the cooked items on the menu weren't available after six, so it was back to the scribble after that short break.
But, eventually, the appropriate times roll around.
With the luggage out of the way, we made our way through Security with the inevitable questionable object identified in the carryon placed there by Madam. On the way out of Townsville, it was a pair of scissors, in Perth two umbrellas.
Equally predictably, she was selected for the random wand-wave for traces of explosive.
Upstairs in the Departure Lounge, there was a chance to sneak in an ale, but at airport prices, you're not going to kill time at the bar.
In hindsight, I probably should've gone two or three more as a sleeping draught, but there you go.