Without getting into too much detail, the most effective way of keeping Australian Aviation safe will be happening well away from an airport. If you are relying on grabbing your baddies on the way into an aircraft you've already blown it. The risk assesment is done by identifying trouble before it arrives at the check in. The security charade at airports that we all have to put up with is window dressing at best, at worst some clown who got picked on at school on a power trip.
The background checks for your ASIC and the unseen stuff is a more logical, effective way of keeping us all secure. While it is annoying we have to go through the same stuff each time we apply and we pay a range of agencies to check if we're on a watch list, at least you know the person holding it is who they say they are. The ASIC should be used in a more logical way with screening for aircrew on flights, after all that's why it's there.
The same logic applies to baggage. Identify the threats before they get to the xray. If you rely on the xray checker to spot the threat you better be sure they're trained well and had a good nights sleep. If you want to save money I'd look at the screening of pax and aircrew first. That and stop reacting and get one step ahead of the people who want to hurt us.