Steve
You did not mention the weather you would be using this in. If you use the pot for melting snow then the surface area of the bottom of the pan is critical, not its volume. I think a minimum of 7" in diameter is required, but a skillet shape with a cover would work well. Its just that most camping pans are too tall for their volume.

I don't think I could cook for 2 in a 1 liter pan, though I often carry a .6 liter for myself on light trips but prefer a liter. Often in the Winter (with 2 people) I carry a double burner stove with a 1 liter and a 2 liter pan and sometimes a skillet, all Titanium. That way the pasta and the sauce are both hot at the same time, or I can use the larger bottomed pan for melting snow while cooking on the other.

BUT I do not like to suffer from taking too little gear. You have to make a decision, do I want the luxury of carrying very little while on the trail, OR do I want the luxury of efficient gear when I am in camp? Since you come from a heavy weight user background, I am suggesting that you may want to compromise, especially if your son is a picky eater, you could offer him better food. (I refuse to eat reconstituted powdered food material while camping because I go out to enjoy myself - I can suffer at home if I want to.)
Jim YMMV