Detonate:I'd really like to photograph some of the more "exotic" life that we don't get to see in the Carribean.
I'd be interested in seeing large creatures, Soft Corals, Lion Fish, Clownfish, Reef Sharks, etc...
Ningaloo has all of that and more...but it isn't particularly cheap (in either time nor money!) to get here or to stay here. For some flight info check out the only airline that flies from Perth to Learmonth (Exmouth's airport) www.skywest.com.au
Cozumel is just so accessible for you and there are always good deals out there it will be a pretty unfair comparison to anywhere, I think. Bali might be a great location for you but I am not 100% sure on the big guys - great colour & macro and scenery.