It’s not a perfect system but what works for me. Certainly should be adapted. Honestly my favorite stop of the year is now. From February onward for about 4 months Central Vietnam is ideal. Mildest weather of the year only occasionally above 90. This year I’ll follow it up with Kuala Lumpur. I’ve been told the weather is mostly consistent there and it has been for my visits in addition even though it’s warm and there can be rains there is a tremendous amount you can do indoors there. There is also very advanced infrastructure that eliminates any concerns about flooding. Rains tend to be intense but relatively short in duration. I think you can visit there most any time. Then I’m actually going to dip back into central Vietnam it will be hot but dry right up until the start of October. By then Cambodia is getting ok but there and Thailand are mostly best by November. I aim primarily to avoid the highest heat first then rains. While I like central Vietnam a great deal I wouldn’t go there October to January. Unfortunately air pollution is also factoring into my travel as well. I would avoid burning season February onward in places like Chiangmai and I’d monitor it in Hanoi and Bangkok in my travels as well.
I retired to the region in March of 23 from NYC planning on doing a retirement visa. But then I visited the neighboring countries and prefer what I’m doing. I travel every 90 days splitting my time between Thailand Vietnam Malaysia and Cambodia. I actually prefer the variety and this way I can avoid the most extreme weather. I’m in Dana g Vietnam these three months. (Perfect weather) Kuala Lumpur the next three months. Thailand 2 months then I might spend 4 months or longer in Cambodia.
How about what they call evacuation insurance. Medical costs are “affordable” here. It’s a risk but maybe not as severe as you might think but with evacuation insurance after you are stabilized here it will get you home.