Get your drinking boots on I think, Barossa has plenty of wineries, couple of golf courses nearby and only a hop step and jump from all things in Metro adelaide, Hills or Riverland.
KI, mostly National Parks stuff such as Kelly hill caves, Flinders chase which includes admirals arch, remarkable rocks. Nearby seal Bay, Cape borda Lighthouse. I'm assuming you can still camp at Flinders chase, if not Vivonne Bay I think has a caravan Park. Plenty of fishing can be done, visit the Parndana Soldier Settlement Museum, watch the locals battle it out in a round of aussie rules, visit the bee farm. Eat a locally grown Marin.
All this and I haven't been since 2000. Some great beaches on the northern side but given your going in winter, it'll be bloody cold.
Both fantastic places to visit, and I'm sure others will eventually give you some more ideas about what you can do that doesn't just include wine wine and more wine!
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