IMO the CA/GRS model at Ballina is fundamentally flawed because it is not an air traffic service (ATS). If it was then Federal law (CASR Part 172) states it can only be provided by the Federal Government agency Airservices Australia. (Why?) Airservices is a prohibitively expensive agency because it has to support a Canberra bureaucracy, everything else required by ICAO, expensive ATS systems and provide a dividend to the Federal Treasury. (Is that why?) Therefore to fill the gap someone in CASA many years ago dreamt up the Certified Air Ground Radio Service (CA/GRS). Used sporadically for air displays at Avalon and in other places before it settled down to only one service at Ayers Rock; however this is not an ICAO-compliant service. An Aerodrome Flight Information Service (AFIS), such as Port Hedland, and used elsewhere in Australia for many years as referred to in these posts, is ICAO-compliant, but it is an air traffic service so can only be provided by the previously mentioned very expensive Federal agency, Airservices. The fundamental difference between the CA/GRS and the AFIS is that the latter is integrated with Airservices other ATS units such as Melbourne and Brisbane Centres hence the duplication of traffic information is eliminated.
The CA/GRS is an aerodrome radio service under CASR Part 139, supplied by the airport, and therefore ignored by Airservices. This results in regulations that require pilots to communicate with each other on the CTAF, and if IFR, Airservices on the area frequency. The radio operator (CA/GRO) then attempts to give the same traffic to pilots as they are providing to each other, but directed, and at the same time radar controllers in Brisbane are also passing the IFR pilots IFR traffic and any VFR traffic they see on their displays (growing in number as more VFR aircraft fit ADS-B). The result is frequency congestion and triplicated traffic information. At Ayers Rock two elements present at Ballina do not exist; moderately high volumes of VFR traffic not actually operating at the primary airport but close enough to be traffic, and low level surveillance coverage. (Now also changing at Ayers Rock due the proliferation of VFR ADS-B equipment) so at Ayers Rock for the moment, the CA/GRS model seems to work. No-one in CASA will accept the argument that CA/GRS does not work in a busy environment because Australia does not have a low-cost alternative to Airservices Air Traffic Control (ATC) and therefore politically they have to pretend it works!
Other more sophisticated aviation nations have faced this dilemma but I will use the US because it resembles more closely the Australian wide-open spaces experience. There the FAA authorises non-government organisations to operate control towers, the so-called VFR Towers. Their job is to handle precisely the kind of issues that occur at Ballina while the local FAA ATC Centre looks after the IFR traffic. According to FAA statistics over 60% of the controllers are retirees from the FAA system, happy to have lower paying job in a less stressful environment.
Ballina could have such a Tower, however the Airservices model would need to replicate the Alice Springs/Hobart/Albury etc model which requires a procedural approach controller in the Tower. This increases the cost of everything - more equipment, more staff, more coordination. The only places Airservices does not do this is at the capital city GA airports that operate very much like VFR Towers.
All Ballina needs is someone in a glass box on stilts with a radio who can organise the local traffic so that pilots do not have to discuss separation with each other, maximise runway usage, and can ensure that itinerant RPT aircraft can operate safely into and out of the circuit area. This is what US VFR Towers do and we can do the same.