Redcliffe or Brisbane have to be the main contenders.
Sunshine State might work too given the club is looking to represent the Sunshine Coast as well as Brisbane, but it's not convoluting the name to encompass both.
But South Queensland, SE Queensland, Sunshine Coast, Greater Brisbane, etc Is too generic for mine. I think North Queensland works because there is a real geographic division between North Queensland and the rest of the state. Furthermore, there are already two other teams in SE QLD.
But does it really matter? I've noticed that the NRL has focused more upon the moniker when referencing teams rather than the place name and putting all the branding on these rather than the geographic name. A bit like American sport, and unlike say European football or even the AFL which still largely focus on the place name of the club.