I think the subtleties do come into play depending on the context. I'm not there now, but like holidaying in Port Douglas, which also has a nice portal to check out the scene at tourismportdouglas.com.au/beachcam and see what's happening.
While thonged females have become reasonably common there, what about me? I probably wouldn't wear one in the main area near the lifeguards but further down I might be bold enough to wear one. I'd would likely choose a less bright colour to compensate for the thong style which is a boldness all of it's own. Or should I go all-out with a bright string that really covers the minimum? Depends on the mood. The more I consider it, the more I'm tempted!
As for nude, Queensland has no legal public clothing-optional areas (Spencer Tunick's recent Brisbane visit notwithstanding) and the Port Douglas Four Mile Beach is open with many walkers traversing the length of the beach. Once when I visited back in the '90s when it was quieter there was a guy at the far southern end who would go nude when he could but covered up whenever anyone approached. Doing the same now would be risky if one was seen by someone prepared to make a complaint. Other beaches may be a better choice.