While I understand that large cities have food shortages and money issues.  I don't see why late game I'm negative income per turn and negative food.

It needs to be made clearer how much money the military is taking out of the economy or something, but still I don't see how owning 15 citiies with all of the money and food related upgrades gives me a crippled economy.  Even looking at the AI armies when I attempt to trade with them, none of them seem to have any money either which means I have no reason to trade with them.  

In the previous update it seemed like the AI was making too much money, while I was still not making enough.  If this part of the game is not broken, then please someone explain to me how it's making the determination.

Also, there never seems to be enough food.  And this has been a problem since the early betas.  How is food calculated?  If I get to the point where my food supply cannot sustain the city shouldn't people start dieing off or something?  Why is there never a surplus of food even after all the research into civilization?