Nice post Mark ! I agree with everything, I spent over 3 years of my life sailing around and I can confirm all this for the boat-related stuff (at that time I didn't have a housing).
Contact with locals is probably the issue I miss most of the time. I tend to want to 'escape' from the human world, and even if I like getting in touch with small tribes and native in remote area, we always try to avoid areas with cities / hotel / crowded beach or crowded with other boats-bays.
You're probably right for you double-gear thing. It will not stop me to have everything in double if I can (at least as a back-up if anything flood/break) and potentially to try using both from time to time, when the dive condition fit; i.e. under the boat on shallow sandy area.
Your point with current is very important. I'll double it, and add that the water will be much clearer when the current come in.
sharks will be there anyway, just not facing the same direction : )