If you want a PPOR you simply need to go and do it now. You more than have the means, you just need to take the plunge.
Otherwise I fear you'll "blow" that $175k on another investment property!
Can you give us the value and corresponding debt on each of the properties? There may be strategies you can use to minimise CGT on eventual disposal if you want to swap them for shares to provide more income.
To be honest, I am sick of investment properties and if I had known about Index funds 15 years ago then I probably wouldn't have bought them.
My plan for reducing CGT on the investment properties was to sell them once I fully FIRE so that my CGT will be on a reduced income. I am not aware of any other means of reducing CGT. Are there other ways?
Property 1: Approx value $480k, Debt = 167k
Property 2: Approx value $420k, Debt = 345k
Property 3 Approx value $820k, Debt = 640k