And the spaceships can be blown to bits by other spaceships.
I think the 6" from marker thing is just fine. However, don't call the marker the scout, call it the battlefield. If a ship is within 6" from the battlefield, it can hit the target designated by the scout. That way, you don't have to put two bricks next to each other or something like that. All you have to do is have a scout and a orbiting bombardment-capable ship.

