Nuts: macadamias obviously. Athertonia are ok, sterculia are also not bad, bunya nuts if you have time to wait, terminalia catappa or cunninghamii are both not bad. or acacia and brachychiton if you want to make flour. Do not try native cashew: semecarpus.
Fruit; fingerlimes, native elderberry are better than European elder, theres a good rubus species or two that like warm weather but could be weedy, davidsonia are sour fresh but make great preserves, buchania kakadu plum, cocky apple, terminalia ferdinandiana, planchonella and diospyros are average along with the native garcinia.
Just a few and remember most bush foods are lacking in selection and breeding. Theres potential if you have time.