I'm offering this as some additional detail on how my migration went - both to get any suggestions on what i should "fix" at this point as well as to provide some insight on what else you might run into in doing this migration.
i'm not sure if my troubles were due to irregularities of my setup, my impatience with battery powered sensors, or what, but this was a a lot of work - and i only had 32 devices - a variety of wall switches, a few outlets, some external plugs, and a half dozen motion sensors. Took me 9+ hours. In hindsight, i think the big issue i had was all related to the 5 or 6 battery powered devices and how long those took to fully show up in hass.
My hass setup is homeassistant core in a venv and i run it in an LXD container so i had to use zwavejs2mqtt server and i chose to download the pkg and i run it inside the hass container - i couldn't figure out the container networking in order to just use one of the docker implementations of zwavejs2mqtt. On the host on which