Very interesting article, would definitely like to read the paper when I get the time.

Something I would like to understand is how these old systems scaled the reference measurements to order of magnitude larger/smaller weights to measure. Up until recently (before the SI redefinition of weight to physical constants) this was an issue even with the modern definition of the kg where for measuring larger and larger weights we essentially have to resort to larger reference weights. And in doing so the manufacturing complexity grows significantly if you want to hold the same uncertainty (as a %). And of course, this applies when measuring masses significantly smaller than the reference 1kg prototype.