Hi,
I have played this game since alpha 19 and have never run into this problem:
I wantet to make a peaceful building town, just so I could focus on builing an not have to deal whit goblins all the time. But now I have played a few minutes and got at a point I wanted some action. But, the onley action i got where some 
who where after my fields. I started Searchign for the command to change the difficulty but all I could find where old post on the forum.
The idea:
There has to be a mod whitch allows players to change diffilculty in/out-game. Like whith commands or a button at the saves menu.
Since I dont know anny coding, I have to find a brave, strong and ferry smart mod maker to help make the idea a thing 