Commuting huh, look at some aluminum or steel frames, and think about using disk brakes, especially if its a wet area where you live. Fenders and racks are big pluses for most any commuter ride, but not absolutely "required", if you aren't so inclined. Maybe some wider wheels than usual, ride quality will be improved, say 32 or 38, even a good 650B would work nicely, and 36h hubs and rims. Some like to use a cyclo-cross frame as the basis for a commuter, that is totally up to you.

I'd check out the commuting forum here, too. Several of the 50+ people are frequent posters there, and this forum has some good people that will have some great input.

I like the fact your wife is on-board, and as long as you are compatible her moving her sewing machine in the work place will be good for her staying abreast of what your sport means to you. You will get some blow back about this, though, but not from me. Best wishes on the project, if you decide to build the commuter, N+1 is usually a good thing.

Bill