Engineering skill set
Engineering spec should be added so we can craft large engines by finding engine blocks pistons and so on and so forth. That way we can craft planes, dirt bikes, and other means for crafting (such as casting stations for the forges to allow you to make swords, milling stations so you can hone broken engine parts) and even metal lathes so you can make Pistons. And super high level engineers get to use a CNC machine. But honestly I really want a plane in 7 days that would be the ultimate transportation like a little Cessna.
