Good to see you here Demmers, welcome.
I'm also working on a "version" of this mod (which Demmers, you should have a link to. I pm'd you about it on Nexus Mods recently). Feel free to use anything I've done.
@mr.devolver Farm Plots work. In my version of this mod, I have a Skill system in place that unlocks all of the "Plots" to address exactly what you stated, cheaper to make. We are also currently using War3zuk's AIO Overhaul and everything works as it should (compatibility wise). Plants right now are the exception and Demmers is fully aware of it.
And speaking of the plants, I might as well bring that up now. The issue is when they grow to Mature status. The Upgrade property is the issue. Ground fertility seems to be an issue also. It hasn't happened alot for us yet, but some plants will grow and not be able to be harvested. Sometimes they "pop" and you lose the harvested item and the plant... leaving the block unable to be planted on again. In one case I've seen so far, Not even going into Debug mode and removing the entity helps.