When you use VIP lane at Suvarnabhumi airport there are four counters and no real distinction between Thai or foreigners. It is my understanding that the long term visa holder refers to the 5,10 or 15 year visa and not the annually renewable non-O visa (even though it is technically a long term visa). The only way to find out is to try though.
at least for the first year. Whether you can use a verification of a monthly deposit from abroad into your Thai bank account depends on your immigration office.
Currently Thailand is going through a difficult economic time and the challenge is to raise revenue. The widely announced tourism tax was scrapped after negative publicity and resistance from various tourism organization. The Thai government is losing tax revenue from rich Thais who are investing and/or working abroad and never paid any taxes. This is why one tax official uttered the idea of taxing global income starting in 2025 after they joined the Global Forum. So ever since there has been talk (again) but after this initial announcement several weeks ago the Thai government has been very silent on the matter, in particular after the uproar it caused. As we have seen during Covid there is always a lot of talk, sadly often uncoordinated, and in the end nothing or something completely different happens. Even with the tax changes about bringing money into Thailand starting 2024 there is still no system in place on how to report it. So follow the news but do not freak out.