OK, let's look at the worst cases... I think this is very worth doing, and that they don't have much to do with preservation age.
Firstly, I'd look at political differences.
The election was interesting, because there were some super announcements that didn't really make it to the news. One was that Labor would cancel the super catch up rules (that you can now add superannuation you missed out on adding for several years), and stop people being able to put concessional contributions in themselves - for instance see -
https://www.canberratimes.com.au/story/6119884/not-so-super-election-promises/?cs=14248.
If we assume that each party will be in power at some stage, and that the promises that they restate at every election are going to occur at some stage, what are the risks to us as early retirees?
I contend that raising the preservation age is the least worry. It has been suggested by various white papers, but neither political party has seemed at all interested. When we will actually have a 12% super guarantee also seems to be a bit of a political football - Labor wants it, the Liberals don't and wages stagnation has made it political dynamite. But if we start to have some inflation, it may be back on the table.
Labor appears to be against several measures that would make it easier to retire early and stuff extra money into super later on. This means that we need to avoid counting on such measures still existing when we retire.
Since the beginning of Howard's reign, the liberals are all for families having just one income, and having a traditional stay-at-home wife. The family allowances were created by Howard to ensure that sort of family had no disadvantages, and many of their measures can be viewed in that context. The ability to put super in your spouse's fund, and the measures I've mentioned already are part of this liberal emphasis on the traditional family.
We also face a problem with the aging population and consequent lack of tax. Labor has it in for family trusts, and I suspect that the liberals will eventually also decide that they are too much of a tax haven. I also think now people can have a maximum of $1.6million in super pension phase, that the tax on super in accumulation phase will increase.
As our superannuation system becomes more mature, and people can play catch-up with their concessional contributions, both sides of politics will see little need for non concessional contributions to exist, and the amount people can put into super will continue to decrease. This has already been happening, and both parties have been reducing these contributions. I would be surprised if you could make any non concessional contributions in a decade.