Potential...
Well, it's cool. Thats for sure. After about 20 seconds of playing i already had a few ideas... first of all, when the pyramid jumped at me, it was complete. So I had assumed the camera would pan upwards if i tried to go over it. That wasn't the case... instead the pyramid lost a giant chunk out of the middle with no warning? Eh, I guess in a second play through I would expect it but... I'm not sure.
Also, enemies would be cool. Not sure how you'd do it. Maybe make space fire where the mouse is. It would be rather frantic if you had to move back and forth from drawing the lines to shooting an enemy.