Another Aussie Hubitat owner here.
I've had my Hub for about 8 months and it's been terrific.
With the C4 Hub you can use USB extension cables to change the Radio's physical locations to maximize performance although I've not needed to.
I've been taking things very slowly, literally creeping sensors into the home so as to minimize push back and to ensure things were a) understood by me and b) stable. But not necessarily in that order.
The Hub has been great. Very reliable, user errors not withstanding.
I'm using it as a home monitoring tool, door/window sensors, PIR's and Wyze cameras but also adding functionality to manually illuminated areas of the home such as wardrobes, under benches etc
Mixing Zigbee and Z-Wave gear but with the Zigbee gear being much less expensive, they're likely to out number Z-Wave soon.
I'm using Google Home but only as a TTS device at this stage until I can convince "others" that they're not being spied on.
Bang for buck - It's an explosion !
Go for it.