Couple options come to mind that are more "wife friendly". I agree with the Parkview in Twin Lakes as an option. You could stay there, and take an overnight trip to the Mariner North in Copper Harbor. She'll like the view from Brockway Mt overlooking CH. Stay there and head back the next day.
If she's not the type that will put on 150 miles a day, make Houghton/Hancock your home base. You can go north or south out of Houghton. Also if you are not going to be putting in terribly long days, having a home base in Houghton will allow you to go out for dinner/drinks and have plenty of options. The Ramada in Hancock is a good place, modern hotel feeling. I've stayed at the TravelLodge in Houghton, not bad. A little older than the Ramada, but bars/restaurants are within a short walk, like the Library, Ambassador, Douglas Inn, Keewenaw Brewing Co, and others. Houghton would get you the miles you're looking for, and allow you to get your wife some creature comforts. And you'll have options for Valentines day, if you're looking for them. Just my $.02.