With regard to the Tennant Creek position, the decision on whether you flew or not was often based on whether the hospital had a nurse they could release to be the flight nurse (they had to pay overtime).
The flights were mainly patient transfer (mostly to Alice Springs but very occasionally Darwin) but could also be emergency evacuations and recoveries. This could include having to fly to remote indigenous communities or cattle stations at night where one needed to bring along their A game skills as they were black hole approaches.
The aircraft I flew there was well equipped and well maintained. That is not to say there weren't issues but generally I had confidence in the machine. The flying can be challenging but was not massive in terms of hours. Most months I was there I only flew between 20 and 40 hours - the limitation being the availability of a flight nurse as the hospital was short staffed when I was there.