If you feel like a walk, Waimak Falls hut in Arthur's Pass is one of my favorites. It's a bit of a walk to get there though.
Barker Hut, up the other side is also lovely.
Apart from the distance they're both pretty easy to get to.
Alternatively you could head over to the West Coast, Welcome Flat Hut is pretty stunning, and their are natural hot pools which are pretty amazing.
There's heaps in Tasmania, pretty accessible grades too!