Sure thing. From what I understand now, you just need to show proof of it when applying for the DTV. And from what I understand, it does NOT need to be in a Thai account, but can be in an account anywhere.
You'll be fine in cities - certainly in BKK. I just feel sad for places like islands (Phangan, Koh Tao and such), they are already vastly overrun as it is - with all its negative side effects. I live in Chiang Mai - here it is that everyone wants to live in the "Nimman" or Old Town area, where rental prices have exploded. But if you just venture to some neighboring areas, all is good.
Yes. To an extend I believe that to become the case. But concentrated on the usual regions and areas. Most people just flock around the already overpriced, overtouristic places.
One Alien shows work and income from outside Thailand. The spouse can just be housewife or houseman (without the need to proof remote or freelance work) - that is what they probably mean.
Unknown at this time. I personally doubt it. As usually local immigtation offices only deal with financial evidence when it needs to be shown in Thai bank accounts. Not sure how they would handle evaluating financial evidence from around the globe.
I can't say, but I doubt that to be true. People married to a Thai national were never forced into a specific visa. They were free to chose from all visa applicable to them. I don't see why it should be different with the DTV. In fact, I would consider alternatives to the (cumbersome) marriage visa.
Impossible to say for sure. Depends on how many and how recent your previous stamps. Also depends on your port of entry. Both Bangkok airports are known for causing issues. Land borders or other airports not so much. I always chose to be on the safer side and got a tourist visa - which is cheap and simple with the eVisa system, after an unfortunate situation at DMK airport once.