Part of the problem Capt M is that CASA put rules in place that they cannot manage or enforce.
Part 139 is a mess because it only addresses Reg and Cert aerodromes and does not cater in any shape or form for ALA's, and hence we have the problems of not having GNS approaches at these airfields (like we once did) and the problems associated with some control over obstacles such as wind farms.
CASA need to do something about this, but then it seems they don't care much about the problems of GA.
I should add that we need to have 'recommended' procedures and not enforceable strict liability rules which only serve to scare flying folk away. If more procedures were recommended as in other parts of the globe, then it is likely that compliance would be somewhat better and we would not have to engage the legals who known nothing about aviation. Again, that is another fight with the said 'culturelock'