I'm going through this right now, but on a pure road style century bike (so fewer choices, yet still very many).

My short list for a tourer would be a super compact triple, something like a 26/36/48 pulling along a 9 speed 12/27 (or 12/29 if hilly) shimano compatible cassette, run by your choice of C11 chorus brifters or bar ends, mated to GS ultegra RD (possibly older indexing MTB RD if you went with the 29) . Would run the FD on either a bar end or DT shifter either way for a tourer. No special chain tools would be necessary. Would mate that to an ultegra hub with appropriate choice of rim depending on your preference for tire width. Paul brakes with koolstops. Bars would be nitto noodles, saddle (for me) would be either a sella rolls or old fujita belt. Sorry if my choices scream utility over grace, but with a tourer I would stick with what I know and what works for me.

It's all upside, as few of the choices you make can't be undone, and your wife has already made you the big winner.