In general, given the technology level that your goblins operate at in, farming should be more labor-intensive.
Currently, the farming system makes it most economical to have a few large farm plots, because in addition to planting and harvesting, the only labor cost is tilling, which is done once per plot. I'd like to suggest a simple fix to this: one tilling job per, say, 3*3 area of farm plot. This would tie the labor cost more closely to the actual area being farmed, as opposed to just the number of farm plots in existence.
We might also let players deactivate farm plots. Add one more checkbox to the screen where you select what seed to plant, like "Fallow", which means no planting and tilling is done.
Further, I posted earlier about a system to keep track of the fertility of your farm plots, an idea which has been received with a thunderous silence. One intermediate step toward introducing at least the semblance of fertilizing, and better farming in general, would be to add a filth-dumping job to all the fields being farmed, similar to the till farmplot job already in existence. I'd suggest the Early spring and Early summer routines, at least, should start with a dump filth job, followed by a till farmplot job. That would make the farming, well, more farmy, and bring the labor requirement a little closer to what I think it should be.
