List ends up as thus:   Atlanta, Ga., San Francisco, CA., Seattle, WA., New York, NY., Orlando, FL., Nashville, TN., Las Vegas, NV., Portland, OR and Minneapolis, MN
What would I change?  I'd leave in Las Vegas but I'd also add Reno.  Las Vegas is rather plastic and fake, built in a part of the desert where no city should be, but it is probably the "most different" experience one can possibly get in any US or Canadian city.  (I'd put Orlando in second place "different" behind it, but not at all in the same way, but both Orlando and LV are ultra-heavy-duty oriented to tourists.)  Reno is a "real" city that actually feels like home.  Keep in mind, too, that these different cities provide different opportunities.  I would definitely add a few to the list:  Chicago IL, 
Ann Arbor MI, Pittsburgh PA, Raleigh-Durham-Chapel Hill NC, Denver CO, Providence RI.  (As a bonus, Boston/Providence/New York NY are all reasonably close to each other.)  And throwing Canada into the mix, I'd add Toronto and Vancouver before I'd add ANY of the ones I just added/changed.
CLIMATE-WISE, I consider Seattle and Portland (and, in Canada, Vancouver) to be the all-around winners.  Neither too hot nor too cold but, because all of these places have sort of a monsoon season in the cooler parts of the year, few people would agree with me about their climates.
In Canada, great side destinations not to be missed would inclide Halifax NS, Quebec City (but knowing your French is VERY helpful there...as well as in the eastern and northern parts of Montreal), and Victoria BC.  I consider Victoria possibly the most beautiful North American major city.  And, as a whole, I consider British Columbia to be more beautiful than any other Province or State.
the Grand Canyon in Arizona is a must-see, and reasonably close if you visit Las Vegas, but don't even 
think there's anything to *DO* there.   Abvout all you can do is LOOK and enjoy the view. 
Oh, and Los Angeles!!  That city is in a desert, too, but it has evolved into a more well-rounded and complete metropolitan area than Las Vegas. 
And don't underestimate New Jersey...NOT AT ALL.  I love it there, and always know that when I'm heading there, I'm going to have a great time.  It's actually on my list of potential retirement places, and from a lifetime of traveling I'm "going into" that list very well-informed.