Should be fine. No minimum income is asked. Just the at least 500k THB in savings + a work contract mentioning you are free to work remotely from Thailand / or a company registered in your name.
Good question. Still not fully clear. It seems that some consulates in 3rd / neighboring countries do accept applications from foreigners / non-residents, others don’t. I have yet to see / hear of the first success story of someone successfully having gotten a paper sticker DTV in Laos, Malaysia, Cambodia, or Vietnam. Maybe this question will be answered in a few days when people report their experiences.
Either proof of a registered company in your name, or a current letter from an employer stating the freedom to work remotely from Thailand seem to be the most commonly accepted ways so far.
They used to actually ask for proof of a booked flight by means of an uploaded ticket. Now, with the DTV, there is no such upload requested anymore in the eVisa system. You still have to fill in a flight number in the form, though. I guess they just re-used the same web form. You could try and just submit a flight number of a flight you aim at taking, imho. Good chance they won’t ask for additional proof. Some consulates might however still request such proof - I guess to ensure that one is actually applying with the “right” consulate in the country one is flying to Thailand from.
Yes. But not because any hard limit on entries or max times allowed is anywhere to actually be found in any Thai law - as I elaborated above. Maybe they finally stop that bad practice of denying people entry for a reason not covered in the law and stop automatically assuming that people with too many visa exempt entries either don’t have enough funds or work illegally. Or maybe they will just continue doing so. Remains to be seen.
The law is called “Thai Immigration Act of 1979”. Section 12 of that law lists exhaustive reasons to deny a person entry into Thailand. And while deny of entries happen despite the fact of there not being any hard limitations, it is hard to defend yourself in that very moment. The Thai Immigration Act also gives the right to appeal against a wrong decision by the immigration officer (I believe regulated in section 22 of the Thai Immigration Act) and a dedicated appeal form exists for that - but hardly anyone makes use of that option as it gives them 7 days for a superior from the ministry to respond. And those 7 days you would likely spend in detention. Who wants to risk that.