Automatic mask creation for sculpting

This is what I suggest: If you go from object mode to sculpt mode, same as it is right now. If you go from edit mode to sculpt, the unselected faces or vertices will be masked automatically.

Creating masks in cumbersome and inefficient in many cases, especially on hard surfaces.

What I'm suggesting is the Maya way. If you select vertices and use the sculpt tool, only the selected vertices will be affected. If you select the geometry, then everything is. It's really efficient.