Not ideal. Lots of transactions must be carried out at the branch where your account is held, so that means many trips to Bangkok. Plus any withdrawals made outside of Bangkok will cost 15 baht each
You can apply either for a "married to a Thai" visa which requires 400k baht in a Thai bank account, or a "retirement" visa which requires 800k baht.
Be aware, if you're getting the Australian Pension, if you become a resident of Thailand you will lose the tax concessions, and your pension will be taxed at 30% in Australia
The only thing to "worry" about is if they suddenly decide they wish to interview you! Bit difficult if you're out of the country, and you kiss goodbye to your application fee!
If you have a UK passport which you will use for your visa application, your police report will be from the UK. It seems you're trying hard to complicate this matter. I've lived in five different countries but when asked for police report I use Australia as that's the passport I use for visa purposes in Thailand.