For most Australians wanting to visit family abroad, it doesn't have to be hotel quarantine or no quarantine - we have homes here (well, except me, but I'm sure I could sort something out). Why not start with the baby steps of quarantining at home?
My point was they could do a study first to assess the risk. If all well then allow vaccinated residents to leave and return with testing or some form of limited home quarantine. But in the next few months could set up a study to understand the risk and give confidence in relaxed restrictions associated with vaccinations.