We have been to Brisbane a few times before so familiarity probably makes me rate it lower than it deserves. To me it's just another city. Having said that South Bank is a few minutes walk from where the shuttle drops you and is quite a lovely place to spend some time, including a fun swimming area with artificial beach. The dock is a long way out of the city and if you don't have a tour organized you should get a shuttle.
We took a shuttle into the city and back and had a walk around. A clean, fresh city, it was nice. Then we took the Kuranda scenic railway tour. This involved a bus up to Kuranda and we took a walk through the bird park. This was well worth the visit and highly recommended. The scenic Kuranda railway was also enjoyable and highly recommended.
We fell in love with Darwin. I think we were there at the tail end of the wet season so we missed the afternoon downpour. We hired a rental car and may our own way around and had an absolutely wonderful day. If you do have a car and have at least an hour take a walk through the botanic gardens, simply beautiful. Also, if you are there I hope you get to enjoy the sunset, it is something else!