Hey there Mr Ham, what's the gear range in gear inches of this proposed setup?
Even with 700 wheels, a 32/42 must give maybe 20 gear inches as a low, which is good.

I ride a bike in winter that I really only use the 32 and 22 ring, and while this bike doesn't have a Speedo, it's top end is not great, I wouldn't want it on a touring bike.

doesn't really make sense to me not to use a double or triple but let's face it, you've got your mind set most likely.

again, what's your gear inch range please.
oh, and honestly, you're going to have some really big jumps between gears, which from experience of many decades riding, would really piss me off, especially with a touring load- you know, spinning too high in one gear and lugging your knees in the next gear up..... this is waaaaaay more important than a lower top end by far, in my opinion.