The OP has been here for 30 years. I assume he has some money in Thailand and is familiar with the banking system. We don’t know but I doubt he is concerned about keeping his money in his home country bank to qualify for an O-A.
Yes you can get 2 years on an O-A. I got an O-A in 2017. Then I got my 1 year extension . You can get the same one year extension after 90 days on a non-O. The OP has been here 30 years. He just wants to continue living here. All the other features of an O-A are probably irrelevant not to mention the difficulty of returning to his home country during this time of travel restrictions.
Both visas can lead you to the same 1 year extension. For most people living here full time that is the goal. If you have been here 30 years then that should be your goal. You probably are comfortable with the Thai banking system. A non-O will get you to a one year extension more quickly. Insurance is not required. Of course you can have insurance but that is your choice separate from any immigration requirements.
An O-A is a multiple entry visa. In the first year you have to wait for the visa to expire. Leave just before it expires and come back after it has expired. Same if you are on an extension and purchased a multiple entry permit.
Yes. This has been the policy for several months. It is also a good reason to apply for your extension as early as possible so that you have time to fix any problems that may arise.
If you have been living in a Thailand then it sounds like you are on a 1 year extension of stay. Did you apply for your current extension of stay based on retirement or marriage? If you did it by marriage then I think you don’t need to have insurance.