Originally posted by johnjwren:

thoughts?

Yup, I second that.

Plow was a thing, if not sophisticated. A simple scratch plow was known pretty early and was basically a few stcks tied together. Cereal/Pulse/Flax domestication is in Neolith while Rye domestication in in Copper age, so placing the plow tech somewhere between them as late Neolithic or early Copper technology makes sense.

It can even be men propelled, same as sledge, until donkeys, cattle, and horses are unlocked.

Originally posted by johnjwren:

it could increase yield? shorten time to plant crops.

More than anything it should reduce the amount of human labor in the process resulting in reduced morale drop from field works. Subsequently, less time will be required for morale restoration thus freeing people for other tasks.

There probably should be a limit to where plow can be used due to field configuration. Currently it's 1x1 min and 5x5 max and allows unused spots, so perhaps a field suitable for plow should be:

a) continuous without any "bad" sectors as the plow will not be able to go around them),
b) rectangular (but not necessarily square) as the plow will not be able to work with "pockets",
c) at least 5 tiles long in any direction for the plow to be dragged along without having to turn around too much.

If all criteria are met, there is no reason why 1 person with a plow can't do what takes 5 people without a plow.
If not, then the field still has to be worked manually.

Originally posted by johnjwren:

...and turkeys...

Turkey is a New World thing unknown in Europe until... idk... 18th century? Maybe Native Americans domesticated turkeys earlier, same as llamas, but the game clearly shows a European culture of Celtic / Germanic type with stone circles, outfit and hair styles, so it seems like turkeys would be as much out of place there as llamas or kangaroos.

Poultry and eggs (highly perishable, like milk, but coming regularly at the price of grain perhaps in order not to wreck the food balance... or at the price of having to feed the dogs with meat) would be a good addition I think.