Awesome Lud. I have not been there in years but my first ship was the M/V New Orleans and that was also the home port. Spent a lot of time there. Can't offer any bars or safe locations. But do suggest the regular stuff. Don't use gypsi cabs. Uber or regular. (Uber is gonna be cheaper. Accent will identify your friends as tourists right away. So no "I got what ya want. Just follow me down this dark alley" (I know but after a few hurricanes (local drink of choice) folks let down their guard)
Jackson Square is a sort of huge and great shopping mall. And to get more of a feel for the real culture, across the river is great fun. I strongly suggest at least a day boping around out side the city if they are into really experiencing that part of the world. Cajuns are a fascinating people. A great many have their front doors facing the water side of the house and not on the road side. The music, food and hospitality is simply amazing and a guaranteed good time.
If your friends get up my way, (CT/NY area) Please give em my number and will be a happy host. Any friends of your's, well are gonna need help.... Snork, kidding buddy KIDDING!)
Of the 5 places in the U.S. I would suggest going, New Orleans would be number one or 2 and they will have a great time! And this is the best time of year to go. Mardi Gras is over rated in MVHO. Just to crowded. Now, not to hot yet and ya can move around easily. But crowds kinda bother me so not the best to ask about festivals, etc.
I'm sure some one local is gonna offer better specifics.
Really kinda cool of ya to look out for them like this, Lud.
Post pics!