Lots of hate for Nassau tends to be typical and makes me a sad panda
There are so many great things to do in Nassau! Here are some of my favorites:
Versailles gardens, also called The Cloisters (google it - it's GORGEOUS and a great place for a photo shoot).
Melia Cable Beach - Beach Day "excursion". The hotel allows you to rent out loungers and palapas, giving you access to the resort, including it's pools, changing facilities, restaurants (including starbucks) and anything else you could need. You can get your wristband at the front desk.
Graycliff hotel chocolatier tour.
If you have connections, the One and Only Ocean Club is a great place to spend a day too.
Atlantis is not too shabby if you have a family and want to take the kids (preteens or teens) somewhere unique - I'd get a jump on a Florida Resident Rate. They often have rooms between $99-$129 if you get them at the right time.
Bacardi Distillery Tour - though it's been years since I've done this, it was enjoyable.
There are also some great restaurants and bars in Nassau. The Daquiri Shack is fun and Paolo was a top 10 award winner in one of Bacardi's worlds-best bartenders competitions. There are a few food tours that are enjoyable for those looking to try some caribbean foods.
The Bahamian people are plenty friendly, but dependent on tourism. You definitely will see lots of people offering to braid hair, sell knock-off purses or invite you into their shops, but if you're not interested, a simple "no thanks" and you'll typically given a "God bless ya child" in response.
I really hope you don't spend your day on the ship as there are so many things to see in Nassau. It's not my favorite Caribbean island, but it's a ton of fun, and not even close to my least favorite. I'd put it in my top 5.