I'm responding to the OP's question. We could go on forever about "if's and buts". Fact is he wants to spend 6 months in Thailand in each year of the next two years. It's a no brainer.
It's the obvious choice for your two-year plan. I've no idea why others are trying to push you onto the LTR visa. That's for a ten year plan, and the non-O is good if you plan to stay in Thailand for most of the year, not for six months. These guys have no idea what they're talking about
Plenty of speculation! Now back in November the government was thinking about a 90-day visa free entry for Europeans. Seven months on, and suddenly.......nothing has happened. My advice to people is not to hold your breath - the Thai media is infamous for jumping the gun and glorifying any proposals. In the long run it'll probably turn into a 60-day visa exempt for the next six months, or something along those lines