Definitely, don't get me wrong, not trying to be a debbie-downer on this experiment. Its a good idea. I think experimentation is one of best parts of the Social Web! I'm just participating to help develop the concept, pointing out things where a different perspective might be helpful. :)
If this community were to start and I were to be a moderator
I stand by that wholeheartedly, a community needs a few people really to be committed to its success for it to not become a junk post community, or worse stagnant and abandoned. An orphaned community from the beginning will ensure it's failure.
I'd put my hand up to help, but i'm pretty full up already, and have been neglecting commitments i already decided to put on myself. But I'll definitely jump in to support where I can.
Maybe some of the c/melbourne regular discussion peeps could help out with building this community. Taking on a kind of active moderator role?
Better make sure the admins are aware of the discussion of this idea. At the end the day its their decision to add a new community AZ.