None of the above. Get off the ranch and explore more of Thailand. The last three are overblown, and boring. Bangkok has its charms, but Thailand has much better than all these.
“A person with a non-immigrant visa and a work permit valid to work in Thailand for at least one year may import one new or used vehicle for personal use.”
You may be able to with a Retirement visa as well. People do drive from Europe, some have gone through Myanmar, and before Covid it was possible to go through China, via the Karakoram road from Karachi. You might be able to drive to Egypt, and put it in a container to Karachi from there. No way would I drive through Afghanistan or Iran, and the northern route through Russia? Not on your life. But for sure, whatever you do will be an adventure.
Get a hybrid. Don’t get a retrofit LPG, it is likely to be shot. But...nothing beats a diesel reliability and generally fuel economy is higher anyway, despite fuel price.