Mr Approach,
all they need is some authority instead of the half-baked situation that currently exists.
What "authority"? Are you suggesting they could direct aircraft around the sky?
That would be half-baked.
The current situation is not half-baked. CAGRS/AFIS do/provide exactly what's in AIP and it is gin-clear. If the individuals are overstepping the mark, that is a standardisation issue, not a fault of the setup. Similarly, if pilots don't know what's going on that is again a standardisation issue.
Because pilots are still obliged to talk to each other within the CTAF,
No they're not. They are required to broadcast. If I've acknowledged the traffic given to me by the AFIS/CAGRO and there is no confliction, I say nothing apart from the mandatory calls (Balon, only two weeks, remember).
Are you trying to say that no airport has ever installed anything unless it was required by CASA?
Pretty much. You have operated sheltered life if you think Aussie airports are top-notch and have done everything they could to enhance safety/make pilot's lives easier.