There is a bunch of wildlife at Barnbougle; you'll see wallabies on the golf course throughout the day but especially morning and evening, and I've also seen wombats after hours. But, there are also snakes, so you can't just go off wandering aimlessly in the bush. I am not sure if they have some sort of organized wildlife viewing tours but I would write to the resort and ask, it seems like something they might be able to set up.
The beach is beautiful, but the wind usually makes it tough going. And the water is freezing, which is just as well.
Lost Farm is a very comfy resort, with a spa.