Sounds like a trip I'm planning myself. Have you looked at a site called Active Captain? If it's an anchorage, mooring or dock it's probably reviewed there in the interactive guide. It's also free to join and use. I use it all the time and I'm a marina review writer for the Atlantic Cruising Club. One of the weak spots I've found is information on anchoring and moorings. Perhaps because there's no monetizing for anchorages. I also do some reviews on anchorages on my own website, but so far just in Narragansett Bay which you're already familiar with.
Enjoy your trip!