Thanks Nigel. I have a bunch of different Chinese modules that use JST connectors for I/O....and I have to say I hate them. Without a matching pigtail, they are almost useless, and even with a pigtail, grafting one to an existing transducer cable is inelegant.
If you standardize on one size, and keep an abundance of pigtails on hand, it could work, but I'm hoping for something a little more polished.
But that does give me an idea. I do have a bunch of 4-pin connectors and jumpers that Elecrow uses in their "Crowtail" system of module interconnects. Using those on pcbs would be handy for test and development and "informal" use, and soldering a pigtail to an "aviation connector" when putting a board in an enclosure could work nicely.