I'm going to guess that since you have 60 views and 0 responses at this point, that I am not the only one totally confused by this post. You have the barest bones of a case study, start off with a very broad question, but by the end have penned yourself into such specific options that I am a little nauseous from the spin.
You lost me, man.
To try and get somewhere with this, here are some things to think about, regarding your case study:
1) $100k of annual spend would generally be considered to need $2.5M of assets. Granted, the 4% rule was formulated on US data, but how do you conclude 1.5M is enough? I understand you have said you wanted to work part-time, but you have included no detail on what level of income that will bring, or what changes you may make to post-FI spending.
2) A $1.3M house is just not Mustachian. Even in a global coastal city. I think numbers like this are going to lose people here, even if It's affordable for someone with your income.
3) Your rentals are just breaking even, apparently without even considering maintenance and vacancy cost. And, a quick Google search comes up with a lot of recent articles that Australia's property market has peaked, and will be declining for the next 12-18 months. (and, in the context of a lot of global worries, too) You also have a majority of your wealth tied into these low-yielding investments. How certain are you about them?
4) Of your options posed at the end, #3 has to be the worst. Cash-out Refi's of secured debt to buy risk assets 10 years into a global bull market that is definitely showing its age? That is the quickest way to 0, not FI.
Given the information presented, my answer to your original question is that the quickest way to FI is to stop trying so hard. You are already above your target asset level. Sell your investment property before the market cools another 10% as more supply comes online. Buy some simple index funds. And buy a reasonable house in the next year with your giant income. Or, move into one of your rentals, particularly if the market makes them hard to sell. You don't have to get fancy.