I've not used this yet, but was immediately intrigued by the idea of it and will give it a go on my next play.

If you don't already, might I suggest adding a little flavor where you encounter broken remnants of machines and on rare occasion you might find a damaged (simply health, not some new mechanic) machine (boilers, steam engines, assemblers, inserters, etc. etc.)? The higher the tier, the lower the chance; you might find a tier three assembler or a centrifuge but at a low rate (e.g., 0.01%).

Nothing to realistically shift gameplay... just a little spice, with mostly empty factories save broken remnants.

"Ooh, piece of candy!"

I like that idea. Adding a bit of a treasure hunt. I will add it to the to-do list and see if I can get it to work.

In case you dont know it, there is the AbandonedRuins mod, of course the ruins are spread in the world, not in the lost factories. But maybe you can steal from/integrate with this mod ;)