I've never been up to the far north, but I am wondering if it is possible to fit Mae Hong Son and Pai into a 5 night Chiang Mai and Chiang Rai visit? Would you guys recommend MHS and Pai, or just stick with Chiang Mai and Chiang Rai? Fly or drive?
From my super quick research, it sounds like 2 days is plenty for Chiang Rai as there is not a lot to see.
IMO, if you fly into Chiang Mai on a domestic or regional flight in the morning, 2 nights is enough to see the sights. If you're flying in from afar, then 3 nights would be better.