I went there a year ago, back in November and it was a really cool area. I don't rock climb so I cant help you out there, but there are loads of really cool hikes. Some places can get kind of crowded and are a little touristy, but if you do some of the more demanding hikes you wont have that problem.
Watch out for snakes, funnel webs, and Bull ants (also called jack jumpers). On my hikes we ran into numerous brown snakes (2nd most venomous snake in the world). Sydney funnel webs (the most venomous spider in the world) are also all over that area.
There are a couple places where you will run into eastern gray kangaroos, which is always cool.
Its a beautiful place, you will definitely have fun.