Toss up between Howard and Keating.
Howard put through the gun laws and the GST but Keating put through superannuation which has really helped every subsequent government with their budget.
Going to go with Howard but that's simply because I'm biased. I still have loads of respect for Keating RE: super.
It still bewilders me that people think Howard was a better prime minister than either Hawke or Keating. Howard led australia into two wars (yes there was bipartisan support, but that's not the point), presided over a near unprecedented period of fiscal profligacy and a hollowing out of the tax base, largely through mostly middle class welfare programs (first home buyers grant, baby bonus, family tax benefit, 15% long term capital gains tax that ramped up negative gearing), fucked the privatisation of telstra, and botched the Northern Territory intervention. The economic merits of WorkChoices are dubious, and considering it was repealed before it really took effect we'll never really know. Let's not forget the Children Overboard affair, either.
When you compare Howard's reign to the heroic reforms of Hawke and Keating, especially in considering how many of these policies were at odds with the ideological underpinnings of the Labor party, it's quite clear that Howard was an absolute minnow. Howard's gun laws were as brave as they were politically opportunistic and astute.
