Greetings,
Congratulations! "Our not so well researched plan..." Sometimes, those are the best plans, up to a point. You have from now until your departure to actually do some more research. Watch the weather and the tides, get tow insurance, current charts (paper chart books or charting electronics of some sort) and maybe take a few USPS courses. Do a bunch of day/weekend trips. It will all come together. Enjoy!