I was thinking that graveyards and crematoriums could be modded, such that they turn normal land into farmland after a period. Also, crematoriums should generate electricity.
Nice....I am seeing a Soylent Green theme.
XD are you crazy, burning people for electricity....
"its people"
Just reroute your waste water output from the river to your desired field.

Might want to keep people away for a few days though.
That would make a lot more sense. It would certaintly be cool if farms develop better around rivers.
What effect does the color intensity have on the industry that develops there? Do farms grow more of the resource if the color is darker?
My biggest issue is with the ore/oil, though. It seems unrealistic that a zone will be depleted in just a few months. I'm still waiting for a mod that makes them infinite.
Yup, it seems the more abundant the resource the more likely a production facility (extraction) will be placed instead of a processing facility, but its seems they can appear everywhere.
Yup, I've place a small industry for my only oil patch in the map (one really dark) I didn't even notice and it went completely away before I could check it, but it also seems extraction buildings remain there and continue to work.
I any case, you really only need a small portion of specialized industry to supply your main industry.