The main issue killing GA is cost, nothing much else will save it. Yes regulatory burden adds to this problem but the driving factor remains cost of operation vs what can be charged to cover such costs.
A small step in the right direction would be to deregulate GA aircraft up to 4.5 tons for private operations and training exactly like road vehicles.
* Relax maintenance standards for private and training aircraft. We used to do 100 hourly oil and filter changes on PA28s, never had one engine problem in 10 years I was there, then came AD-ENG 4 and we had to do 25 and 50 hour changes, depending on equipment.
* Relax security measures and requirements for private and training operations, ie airports like Moorabbin should not need ASIC entry requirements or ID cards etc, just photo ID on request so a drivers licence or pilots licence.
* Merge RAA and GA to 4.5 tons, one rule set for all private operations (to the lessor standard) none of this stupid, oh a 700kg has less mass and inertia than a 1000kg, we know that. Anyone can drive a 4 ton loaded truck with no training or security, with the possibility of crashing into a bus stop or bus with the chance to injure hundreds, let alone do something 'illegal' with one.
* Get rid of liability issues and extend the limited liability to include all private/training aviation, only gross negligence to be covered. It is something you choose to do, knowing the risks.
* Get rid of liability issues for private and smaller airstrips, covering only gross negligence.
* Return all theory up to private licence accreditation to 'in-house'
* Mandate all significant majority GA airports to cater for and foster the growth of GA operations, including set aside areas for parking including affordable maintenance, storage and operational hangar space.
If these measures work for Private and training operations without planes dropping from the sky (which they won't), extend them to small charter ops etc.
Further things to do,
* Fund the resurrection of the local GA production and maintenance industry.
* Fund country infrastructure and tourism to include building airstrips for private visitors.
* Change taxation rules around light aircraft.
* Fund local light aircraft production.