Good thread.
Tange Champion #2 with a max weight of 200 lbs was what Centurion selected for use in their full-on touring model (ProTour) at least in 1984. When I did some loaded touring the "rider&gear" was about 250-260. The wheels were 36 spoke, box section Araya and seemingly bombproof.

We all know that tires/wheels are the contact points for our weight - so choose those with more caution than a frame.
Who has a chart on spoke weights? (edit: just kidding)