I think the ideal computer desk design is a drafting board. A 3-foot wide by 2-foot deep flat inclined surface that you can draw on. This is just about possible today. You need two projectors, one on each side, projecting the screen onto the 3'x2' surface. That makes it harder for your hand to block any part of the display. You need something to sense the position of the pen. A cordless keyboard probably helps too. Other than that, it's just a normal drafting setup.