Brilliant idea (and execution), LBD! Your ZCIs are very efficient in terms of both materials and time-to-swap,
When I got my Grizzly G0899, I knocked together a few inserts from some plywood scraps. It was a pain because of how close (around 1/8” or so )the little mounting ears are to the top of the table. I didn’t route the thicknesses of my inserts exactly the same, so I have to re-level them with the grub screws every time, which is a complete waste of time. Something like this, or something similar that uses replaceable strips with the stock metal inserts, would be a huge improvement. (I saw something similar to the latter in Pottz’s table saw thread.