You won't really know until you turn up here. You have to keep in mind that there were a lot of scams that went in during covid, such as bogus ED and Volunteer Visas, and the perennial "COVID extensions". Any of these on your record will potentially flag you for further investigation. Do as
You have to get used to correct terminology. What you're referring to is a non-O (married to a Thai) visa. The non-O (dependant spouse) visa is if your spouse is also a foreigner. To answer your question, yes you get a 12-month extension, which can then do year after year (provided you meet the criteria)
Stanners states, when you get your new extension in October, it will have an expiry date the same as your passport (June 2024). This will remain the same every year you extend, so you effectively change the expiry date.
If you qualify for a METV you can legitimately get almost nine months in the country with two strategic border bounces. All above board. It's the longest tourist stay you can get without having to worry about immigration officer mood swings