i love this mod and i really don't understand why it's not in the library...( i discover it incidentally, serching for other stuff, thanks to google strange algorithm, whom seem know what i'm looking for, even when i'm not ^^)
Anyway, concerning the farm problem, i agreed that the AI morale\tax problem is a major "bug", but i dislike to see useless bonus tiles: so i have added a lil' food production bonus to market places (the logic is that in a market places were sold even imported food). It's a little bonus so it should prevent the massive morale problem (in any case i think that 100 billion of people can't live togheter in single planet and remain a civil society, no matter how advanced the planet is: try to live in a small place with a lot of people for 1 or 2 week and you'll know....) , and anyway, the economy bonus should balance the eventually lower taxes..
Another way could be add the LIL food production to morale's improvement.. but i prefer the economic one way (i my mind there's no way to feed people with pizza and hotdogs, no matter what yankee say ^^)
Thanks again for this work! i love to see "minors" building great empires