I spent a couple of nights there in July/August - cold, but visiting from Scotland, wasn't too bad for me! I was alone, so stayed at a hostel in Kingscote, which was fine
Done a few walks through Flinders Chase, the touristy walks to Remarkable Rocks etc, all absolutely worth it. Popped into a few beaches along the North East coast, all gorgeous as per. Even in winter...I couldn't help myself having a little paddle at Baudin(?) Beach. Only regret is not staying longer.........can only imagine it would be even more spectacular in the warmer months