things to do in nassau, grand bahama island, and grand stir

[solrac1500]

Calling all vetern cruisers im taking a four day cruise to grand bahama island, nassau, and grand stirup cay on norweigan sky on 9-29-08.
Dose anyone have any good sugestions of things to do? I'm travling with a party of four and were all in our mid twenty's and are looking try something new. We did the Atlantis water park thing last year on a diffrent crusie. (We thought it was over rated, but we are lucky enough to live in central florida where there are about five large water parks to chose from year round) We have done lots of snorkel tours and they are starting to blend together, but we may take one in grand sirup cay because there is not many things offered to do there.
We're defintly leaning towards something a little more exciting like jet ski's, parasaling, and skydiving but we are open to all sugestions.
Also dose any one of any booze cruises in nassau. I know that carnival dose one thats preety fun, but im almost positve we wont be able to do that considering we are on a competing boat.

Thanks ahead of time for any sugestions!