per acre which strat produces the most income?

ex 3k acre casher 3k acre farmer 3k acre techer

also, how much food does unbuilt acres each make?

Depends heavily on tech/food/mil prices, but IMO peak production would be an early techer. Late set probably casher. You also have to factor in the cost to convert your goods/cash into stock and back (which makes the farmer the most efficient, as you avoid the conversion of goods costs. but farmer has a slow startup as the production/acre early is poor, possibly lowest of the three comparisons you've made)

And I think it used to be 0.4 bushels / acre for unbuilt land, but hopefully someone who actually knows will verify this.

ty got the answers I needed =)

Yeah it used to be 0.4 per acre for unbuilt.

it still is 0.4 bushel per unbuilt acre