Delivery Man

Those tiles only give you the ability to fly over/under them. They have no affinity with the direction that a ship can fly over them, or the direction bombs/bullets travel through them. Those tiles are really only good for making things look graphically nice.

Walls that can allow bombs/bullets to p!@#$%^&* through one side but not the other. Walls that will allow players to fly through one side but not the other. Walls that act as permanent bricks for a freq. You could do so many more creative things with bases if this were possible.