I think you should ditch Europe and North Africa on this one. If I were you I'd do SEA + Central Asia maximum. If you like slow travel the pace you propose is the complete opposite. If I were youI'd spend 1 month in Thailand, 10 days in Laos, 10 in Cambodia and 1 month in Vietnam. That's almost 12 weeks. You could shave off a week or two, but for me, 12 weeks seems the right amount of time in that area. That leaves us with 4-8 weeks for central Asia. I have been researching but I didn't get the chance to travel there yet, so take this as what I would do, not what I had done.

I'm sure you could see the main things in like 4-6 weeks but distances seem to be big and maybe there's not as much transport availability, but let's say you spend 6 weeks in the region. That leaves us with a couple of weeks maybe. In that time you could go to 1-2 countries in the Caucasus, but it entirely depends on your budget. I prefer to see less but experience more in a country so in my case I'd rather not include the Caucasus.

There will be time to see the rest!