Looking for Answers about Bahamas and Florida?

If you are a US citizen then you don't need a passport. You will need your birth certificate and some form of photo id (Drivers Lic). If you are a foreign citizen then you will need to carry your passport.
Bahamas doesn't require a visa but you will need your passport/birth certificate when you get back to US.
It's always preferable to carry your passport. In case you miss your ship in Bahamas and you have to fly back to US, then you will need a passport.

It sounds like that would be ok, but I am certainly not an authority... If I were you I would contact NCL directly through their toll free number to get confirmation directly from them.

Yes I believe you can, but I would check with whomever you made your reservation with directly.

Local authorities generally do not permit food to be brought off the ship.

Alcohol purchased in ports will be held on your return to the ship, you will receive a receipt for your items, then on the last evening of the cruise you can pick up your alcohol at a designated location.

Yes it does.

Since you are going to have a lot of luggage the easiest way will be a taxi. However if you have a large group you may want to contact NCL and have them arrange for ground transportation from the airport to the pier.

Yes. You are allowed to bring your own sodas, juices and water. You can check them or carry them on board. The products must be sealed or risk confiscation by the security. Make sure you tag them with your bag tags so that they are delivered to your stateroom along with your luggage.

Not at this time, although it is something I have read that NCL is considering.

No, but you can ask your stateroom attendant if there is one available for you to borrow for the day. The ship does offer full service laundry service for a fee.