More storage space for custom designs, so you don't have to have extra characters just to have more than 10 parts of a design. There should be an enhanced design editor that lets you define your designs. So, you say, "this is cobblestone," and the game now knows that the area isn't diggable, but could have presents and other things dropped on it. Plus, it would sound like stone when you walked on it. You could even have areas between cobblestones that you define as grass, and weeds could grow up between them.