You can get non immigrant O visa in Aus’ mate. No need for Thai bank account or 400k in bank.
I recently got spouse visa non imm O multiple entry in Brisbane.
Need Copy of thabian Baan, letter from spouse stating still together, marriage cert, and her ID. Mrs was in Thailand at the time and they accepted photos of letter and ID she emailed to me.
Suppose if you don’t want to leave Thailand the way you’re doing it is the way to go. But I’m in the merchant navy so have to Tavel back to aus to go to work every 3 months.
Bonus is not having to deal with Thai bureaucrats or line up for hours in immigration.