Formersnag, the Greens would actually change a lot if they live up to their own policy promises (and to their credit, they have stuck to their guns). The system of mixed-packages would remain, although on the flipside they seem to be most open to citizen lobbying and less open to corporate lobbying.
My only problem is that I personally have a less enthusiastic stance to the UN and refugees than they do- otherwise I generally agree with them.

But the only answer is to NOT vote Libs, Lab, Nats and Dems- and pick a party or independent that you feel;
1- is actually serious about their job
2- represents you views
3- explicitly states issues they want to reform.

Of course, the one good thing about our system is we can vote for all parties or independents in varying degrees- so you can do what I do and write a whole chart of who you will support in what order.
For me:
1- most prominent parties who correspond closest to my criteria
2- parties that don't, but seem to earnestly endorse CIR, and single issue parties I endorse (Save Our Suburbs)
4- parties I simply don't care about
5- religious/libertarian parties (the worst- but no threat of getting elected)
6- Libs, Lab, Family First, Nats and Dems- if there are any 'small l liberal' parties they can go there too (most disturbed people in the nation IMO).