I do believe the only way around the 800k requirement is to have your embassy here in thailand confirm your income in a formal letter. They'll need back statements etc, plus a host of other forms. I looked into it once admittedly a long time ago but my income far supercedes the 50k or whatever it is you need to prove you can stay here. Maybe you could confirm if that is still the case
If you download Netflix in the USA or UK on your phone or computer you have the exact same in thailand. If you want to watch on a big screen just but a smart TV and you can flip from phone or computer to TV.
Get health insurance anyway. It's stupid not to have any health insurance at any time. It's called accidents and emergencies. Or ignore me and walk into flowing traffic the give me a call.
I flew in recently on a one way ticket and got a 30 day visa. I would however show any onward flight at airport immigration but not sure it is necessary. Of course I did a one way as I'm planning to stay forever. Was just travelling when my non o ran out.