Great stuff!

I may have missed something, but in other industries there's a maximum fill you're allowed for a conduit. What do you guys need to adhere to?

Isn't this the exact usecase for which bus-systems where invented? I mean your processing unit connects to the input/output modules digitally, why not place them where your inputs/outputs are? Or, as you mentioned SCADA, put a small complete PLC into every cabinet and connect them in your SCADA.

I absolutely hate when I unspool a wire and it just ends up wrapped under and around and all over the place... I swear those rolls were made up on the end of shift friday afternoon and they just wanted to go home.... Meanwhile, out in the field, you invent about 5 mew cuss words and wanting to cause physical harm to the person who spooled it. I get so frustrated and anoyed.