Similar to how the Academy of Industry displays the ingots you have available for factory upgrades, it would be useful to see the construction materials you have available to trade on the Tool Exchange gui. I find myself jumping over to the barn to look at my construction materials to determine whether a particular trade makes sense for me. This step would be eliminated. Additionally, although gems are held at the Laboratory and not the barn, gems available are shown in a way that resembles the way ingots are at the Academy making the Tool Exchange interface seem odd.