Some good advice here already. I'd advise starting with the list of places you'd most like to visit. Then work from there in building your itinerary.

I'd also suggest strongly considering Star Alliance (*A) rather than One World (OW) . It has many more member airlines, which would give you more flexibility. For instance, if you decide you want to travel within Africa you'd have South African Airways, as opposed to (I believe) no OW members.

Another reason I'd suggest *A is that it includes Singapore Air, possibly the best airline in the world, especially if you can get flights including its new business or first class seats. On the other hand, OW member British Air is arguably the best European carrier in business or first class. And OW member LAN Chile is probably your best quality option for S. American travel.

But on yet the third hand (??), if you're traveling in F with your wife you wouldn't need the greater privacy that BA seats give you and *A member Lufthansa is very nice in F and you'd have access to its unique, stellar First Class Terminal if passing through Frankfurt.

As for places to go--if you're not necessarily limited to the places you list in your post--I'd highly recommend Cape Town and the Western Cape province in which it's located. Also, New Zealand is wonderful. Paris and Venice are the two most romantic cities we've ever been, with Prague being a close third. Being a native New Yorker who now lives near San Francisco, I'm thoroughly biased but recommend those as the two top spots to visit in the United States (with lots of scenic splendor in California and other parts of the Western U.S., though the best way to see much of that would involve renting a car). Buenos Aires (though be prepared for a huge, sprawling city) and many parts of Argentina are fun. If you want to get to the Caribbean, Virgin Gorda in the British Virgin Islands is very nice.

One big factor you might take into account is what the weather will be like in various places in your itinerary at a given time of year. You'd want to be in New Zealand and Australia in November-March and China in May, rather than vice versa, for instance.

Anyway, sounds like a great way to spend a year!