Taking Recommendations for St. Louis, Kansas City (MO), Memphis, New Orleans

In May, 2011, I drove this Ford Focus from Detroit to Pittsburgh,
over to Boston, and down to New York as part of a business trip to collect data.
In May, I'm going to drive to and through St. Louis, Kansas City (MO), Memphis, and New Orleans. It's part of an annual work trip, and without boring you with details, my role is to drive to all these cities and throughout the day make 11 stops.

All the stop must be at least one mile apart. I have to be stopped for a minimum of 15 minutes. At some of the stops, I can get out of the car, walk around, have a bite to eat, but for efficiency reasons, I can't do that at all the stops. Some stops hold nothing more than 15 minutes of sitting in the car and tweeting (while I run a data collection test on some phones, which requires very little of my attention).

While this will be the third year I take this work trip, each year the cities where I've been assigned have changed. Last year I had Atlanta, Jacksonville, and Miami. In 2011, I went to Detroit, Pittsburgh, Boston, and New York.

My favorite cities for this particular project were those in which I had a wide range of places to stop, like parks, waterfront areas, coffee shops, restaurants for lunch (with nearby parking), museums, major sites (stadiums, historic buildings), so that my day was filled with variety. Otherwise the trip gets boring fast.

So I'm taking your suggestions for where to go in St. Louis, Kansas City (MO), Memphis, and New Orleans. You can add your suggestions in the comments (and note that all comments go through an approval queue, so don't freak out if it doesn't appear immediately).