Dr,
Wouldnt the problem be that there are not that many places for the Feds to put the returning Aussies.And whilst I would have excepted a Van, or a tent in the Desert, I am very sure that the average overseas Aussie returnee would not, at least without a whinge and then a very supportive public outcry regarding a minimum standard of a 5 star hotel.
And even there lays the problem...a tent or Van in the desert would have to be on ground that is generally under control of a State or territory, not the Feds..
MANUS Island perhaps...but imagine the scream from the left about that...just like when Xmas Island was used for returnees from China.
Solution...mmm not from this forum I think, as as great as we are at solving problems......Constitutional change is a huge step outside our gambit.