Having a week is ok but you don't want to spend 4 days of it driving, I would look at Thurra Inlet, got some ripping sand dunes behind it and a lighthouse,lots of coastal views. You can still drive to a couple of other spot from there.
A word on Mungo, had a fried just get back a said that the walls area is all fenced of and technical nobody is allowed in without a guide between they found a bone..
Flinders Ranges would be high on my list too