I’ve rewired dozens of homes like these over the years, but this one has been the absolute worst. sick

Yep! I had 1 Recessed to do once: figured 1.5-2 hrs on site.

3 hrs later!! after false ceiling x 2 then hitting the original 4x4 timber 4.5" above the other 2....AAARRGG!

AFCI should be fine. But you still will need GFCI receps. per ckt. I would think.