although I am not from Aus myself I know 2 people that have sponsored their partner, one was told by the agent doing it for him he needed a minimum of 30k savings with regular income going into his bank, the other was told 20k with regular income, both had no issues getting the visa.
You will need to do a degree/masters/PhD at a university and find a university that will support the applications. Language/Muay thai/Cooking etc schools can not support dependency visas.
you can get 2 license waivers which is 4 years, it is possible to get a 3rd waiver if you can prove you have enrolled in a top up course if you're not a licensed teacher in your home country near the end of your 2nd waiver.
I'll echo what Rob is saying, you can also walk-in to any AiS store and get the same deal, you can even just grab a SIM and set it up yourself on the MyAiS app.
You aren't going to get a non-B without already having the business established, and you definitely aren't going to get a work permit without having 2m in capital for the business and 4 Thais working for you too.
unlikely, all the rules and requirements will probably be announced on the 1st of June but I don't see it being fully implemented and made law before September