I love the idea of this mod, but when I used the locks I was disappointed. The reason is that, if I understood correctly, all the gold keys open the gold chests. The ideal would be to create a custom key using the anvil (currently possible), only changing the name, and, if I lock the chest with that key, that key is the only one that can open the chest.

This would add security to the chests (if all the golden keys open golden chests, there is no real security) and a very fun RPG component (they could steal my key and open the chest with it). You could also "lose" the key, not so much fun for some, a lot of fun for others.