The original title for Missile Command was "Armageddon". Here's a cool piece of concept art for the Armageddon cabinet from the Atari artwork archive that recently surfaced:
So cool, and thanks for the link. I love it when comments connect to related but little-known content that actually expands the scope and understanding of the original story.
That drawing of the Armageddon cabinet clearly shows the secondary info displays and even shows the two head positions of the player. Maybe it's hindsight, but that seems like such a distraction, especially on a game like Missile Command, I'm surprised they even considered it in the first place. It would make a compelling feature in the right game, though I think the displays would have to be placed around the screen.
http://1.bp.blogspot.com/_fWR8DhqQ9lw/R72zO6Q2oEI/AAAAAAAAAK...
More available here: http://metacab.blogspot.com/2006/03/atari-concept-art.html