Builders want more. Let's give it to them.
This idea is from my fellow clans mate.
We have all seen how tirelessly those builders swing their hammer, sometimes for days at a time with no complaining. Sometimes hitting the same spot over and over. Sometimes they get to hit even more things like tree stumps with their hammer. But what if they wanted more hammer time? They LOVE it. Who are we to deny their desire for more hammering? Send them into a mine and let them boost ore production for a time, hitting rocks with their hammer. I think the worst thing a builder can imagine is going to his hut, waiting impatiently for something to hammer.