Very impressive stuff. I had thought about what a StarFox game would look like on the GB/GBC but couldn't wrap my head around how to display the dialogs during the stage without obstructing the view.
And yet you did it flawlessly! This demo was a lot of fun and felt very polished. The pixel art is impressive as well, congrats!
I wonder if you have any alternative weapons planned for the full game, as it is so far mostly a matter of mashing the A button to shoot down the enemies?
Anyway I'll keep on eye on Cosmo Command, it is very promising.