We are going up at the end of May. We'll be staying at Waters Edge apartments which is also on the esplanade near Muddies. I have a great friend who lives there & a sister who lives further north so that's our main reasons for going, but having Muddies in walking distance means we're not hiring a car either, lol! Muddies is just a park with fountains & water play, and climbing/play equipment. It's free (yay!) and has a cafe (yay!) and therefore is everything I am looking for in a holiday activity
I would also suggest getting a car if you're going anywhere further north. (We are thinking about visiting the Daintree for a day and may hire a car just for the one day for that purpose.) It just makes you more free & flexible, especially when you're getting around with little kids.
Have a great time!!!