We have been to the Bahamas six times since 2005.
1. Water. I agree with a lot of the comments above about NOT buying a water maker. We had one the first couple times we were in the Bahamas and needed it. Now it is easy to find "good" RO water. Yes you will have to pay for it.
I also run the hose water thru a 3-stage whole house water filter before it goes in the tank. First filter sediment. Second for bacteria. Third charcoal for taste and smell. I even do this at our dock in the states.
2. Dinghy. You can not have one too big or too fast!
3. Power. We have a 8 kw diesel on board, but use a Honda 2200 most of the time. Our diesel burns 0.4 gph. The Honda burns 1 gal in 10 hours. It is some what a hassle to contend with the gas, but we have it for the dinghy and keep 5 ea 5 gal containers that we can go a few weeks on.
4. We have an apartment size refrigerator/freezer that is the main thing the Honda operates. We shut the Honda down at sunset and start it about 8 or 9 in the morning. If you don't open it all will be good. To test, put an ice cube in a small bowl or lid and leave it in the freezer. I can almost guarantee that in the morning the ice would not have melted.
It was mentioned to spend more time there. I fully agree with that. The Bahamians are great people (especially in the out islands) and it would be a mistake in my mind not to spend a couple months in country if you time will allow.
Have fiun and I wish you a great trip.