I can't speak from a position of authority, since you are where I was six months ago. (Except for the harley bit of course). I'd say that when it comes to your wife, demand the same standard of yourself that you would if someone asked to have your daughter ride along. Which is to say, quite a bit.
1) To start off, you need your endorsement. Take the Basic RiderCourse even if you don't have to. It's basic slow-speed stuff, but it's a foundation for what you're going to do in the future.
2) Pick a lightweight bike to familiarize yourself with, and to take the Experienced RiderCourse on. (And also to drop - some of your candidate bikes are faired, and since you're going to drop it, you might as well not pay to repair the fairing).
3) Get a fair bit of experience riding solo before getting a heavier bike, at least 6 months.
4) Take the ERC on the heavier bike, and make sure you've ridden it for at least 6 months.
5) Then you're barely ready to take someone else's life in your hands.
When I took the BRC - only a month ago - the coaches had a private laugh about people who bought liter sport bikes or heavyweight harleys. Not that they're bad bikes, but those riders have a, let's say, diminished chance of still riding in 12 months. You're at the greatest chance of having an accident in the first six months riding any bike, and you're at the greatest chance of having an accident on a bike that exceeds your abilities, so why rush?