Like I've never been in trouble with her before! (Like most men, I married a whole lot better than she did.)

Actually, Isle Royale is beautiful, but probably a bit too complicated, logistically, for what you want to do. All things considered, it sounds like your best bet would be Yosemite if you decide to go west, and the Appalachian Trail (a single longer chunk, or several selective sections) if you want to stay east.