Please allow me to burn with the ship if this has been beat like a horse, however I recently had an idea on being able to craft signed items, the model goes as follows;
First Step: Harvest all materials for items. After being implemented, each item gathered will now have your name attached to it and will have your name until you choose to use or sell the material.
Second Step: Craft with only materials you've gathered yourself, therefore each item has your name. Similar to how +1 materials increase quality, using only materials you've gathered permits you to sign your work.
Last Step: Crafted item now appears with your name attached to it, proving you've made the material from scratch. Please do not give the use the option to sign it or not, this would just mean an extra step for say Copper Ingots while people are just trying to level up, resulting in a greater timesink for them.
I know this would be difficult, but perhaps it could just be a majority of materials? I know creating an item that is actually useful from material gathered by yourself is very rewarding, this is just my idea of showing that achievement. Thoughts and suggestions? Please note that I wish I knew how to tag the Dev in charge of crafting but this is my first post and don't know how.