I'm yet to read of a real tourist affected by the rule change, only the ones who think they are entitled to live here on free entries whilst others do the right thing by obtaining an applicable long stay visa...
Each time I have left Auckland they have asked for a return ticket at check in, I have a long stay visa which doesn't require one, sometimes that's accepted straight away, other times they make a call, or a supervisor more aware will complete check in.
Genuine tourists rarely complain its those who don't go home and don't qualify for a long stay visa who aren't happy being denied entry as the pretend to be tourists but aren't able to fool every immigration officer by attempting continuous exempt entries .....
The "free" 2nd year you mentioned, will also require the mandatory OA insurance for that 2nd year, otherwise he will be stamped in until the insurance expiry date instead.
Point number 2, how I read it, if the OP already has the 800K seasoned in a Thai bank account, depending on his immigration office, he can go for his one-year extension, with 45 days left on his 90-day stamp in Chiang Mai for example.
Sounds like he doesn't need to use the first 60 days of the 90-day stamp for seasoning?
Your 1-year OA can be stretched to 2 years if you re enter Thailand just before the 1 year expiry date is up, then you will be stamped in for another year from the date you arrive providing your required insurance cover also extends through the 2nd year.
After that to extend in Thailand, your funds (800k THB) will need to be in a Thai bank.