You'd have to go off the beaten track a bit to satisfy your criteria for abandoned towns, resorts and mines. I don't think you've have the time, much less the 4WD to savour the experience of just getting there!
Plenty of rocky beaches, coves and small creek mouths along the Great Ocean Road, not as busy in February as December and January, but requires care for international drivers who are easily distracted by the wild views
Oh, yes, Australia, you folks don't drive on the right side of the road (you can take that however you wish (: ). The area does sound really nice though! Kind of like the California coast with more rain.