1. Be able to form a custom shell for a mouse to tailor the fit for you.
2. This is more of a design idea. Have modular parts that you can put together via magnet/clips or some other method that allows you to custom build a mouse with the parts that you want. scroll wheels if different locations move/add buttons of different sizes on the right/left side. These are just a few examples. Also have moveable plates like a Ratt 7 or have custom size shells.