We were limited by the lack of a car rental, so we stayed at the Sea World Resort, right near everything we wanted to do. We went whale watching, explored Sea World of course, found some really good fish n' chips, and plenty of expensive sushi. While our hotel had this lovely heated outdoor pool, that proved not to be as heated as I had hoped when I hopped in one evening. The staff was really great about a leaking problem in our bathroom, we were upgraded to a room with a view of both that beautiful pool and the beach!
We went whale watching on our second morning in town. The ocean view was spectacular, but I stupidly ignored the sea-sickness warning and got.. Well, sea sick. Despite losing my breakfast, we did see many whales and even a few dolphins out there and that was amazing. The videos that they played on the boat were actually interesting, rather than the less-than-entertaining educational videos that are normally shown on screen. We found this delicious fish and chips place later that day, about at 15-20 minute walk away from our hotel, where you pick your fish raw (it was a fish market) and they cooked it for you on spot. You could also order sashimi, as well as many other seafood dishes. It deliciously made up for the food that I lost to one of those barf bags on the boat.
The dolphin show at Sea World was one of the more amazing animal shows I have ever seen. I find that dolphins always remind me of The Hitchhiker's Guide to the Galaxy. I was puzzled by the dinosaur exhibit, because it didn't really have anything to do with the sea in my books, but it was cool anyway. Sea World also offers one of the largest and tallest outdoor jungle gyms, and an attraction called Battle Boats. Battle Boats were these boats with "canons" that shot out a stream of water as you twirled the handle. These boats traveled a course around the "ocean" (a pool, essentially), and the passengers of the boats could shoot any bystanders who were watching. The bystanders got their revenge, because they were also equipped with canon shooting stations, so we could shoot them right back. It was like a massive water fight with strangers, the whole thing was a lot of fun :)
I would love to revisit Gold Coast, make use of the BBQs that they have stationed in their parks (with electrical power too, you literally just set up at the station and push a button to start BBQing!) and hop into the waters and have a fun day at the beach.