@berniej Thankyou! I'm glad if this is useful for others.
Please note that I have just done some tweaks to the response reading and sequence processing that address a couple of concerns I had, it should be less liable to briefly de-syncing when console (or json) status messages arrive.
There is a new release, v1.1.0 in the repo, the changes are all internal, usage has not changed.
Finally; I got to do some gc.mem_free() data gathering at various points in the loop under micropython; I max out at about 24K total additional RAM consumed by the serialOM loop; even when I have cycled the controller through three modes and run a simulation in each to fully populate the local OM with typical data.
I'm pretty happy with this, better than I expected.