While Macropus rufus is now the largest of the macropods, M. giganteus (Eastern Grey kangaroo) was much larger (3m tall) during the Pleistocene; we now have only the tiddlers among us. Much more common, in the eastern states, their footprint is much lighter on Oz soils so the replacement of cattle by kangaroos has much to recommend it; their meat is much leaner, the fur is warmer and the skins are much more flexible than cowhide. Concertina bellows of kangaroo hide last better than the usual northern hemisphere materials.
Chlamydia is a major problem in koalas but I thought I'd leave the reference alone.