Much of the early development discussions cited that orcs were supposed to be 'at home' in the jungle much as elfs are 'at home' in the forest. This never rally materialized, very likely for balance reasons.
I would suggest the very simple addition that Orc should be able to 'farm' or 'hunt' jungles *without* improvement, allowing them to garner 2 (perhaps 3 due to health problems) food total from any jungle square early on. Since there would be no hammers this would ultimately not be a winning strategy and introduce the civilization/barbarism dialectic into the play of the orc: Yes, you can have great big swarms that cannot produce anything or you can cut the natural food source down and civilize it. Additionally health effects would eventually catch up preventing mega-tribes.
I would suggest the very simple addition that Orc should be able to 'farm' or 'hunt' jungles *without* improvement, allowing them to garner 2 (perhaps 3 due to health problems) food total from any jungle square early on. Since there would be no hammers this would ultimately not be a winning strategy and introduce the civilization/barbarism dialectic into the play of the orc: Yes, you can have great big swarms that cannot produce anything or you can cut the natural food source down and civilize it. Additionally health effects would eventually catch up preventing mega-tribes.