Flapcake, the only way to do that is to increase the size of the map to 900 or more in height. To have the 4 parts of the legend (instructions, air, sea and land) to look nicely laid out would be to have them either spaced out of squashed. I have the 12 aircraft boxes at the top so to have 4 different parts would be 3 boxes across. This would be the only way to make it look nice as different sized boxes in width would look the same as now and then you have to ask, why change.
The Rules of engagement would then have to be squeezed into a slimmer space.
The land forces could go on top of each other but the lines would be closer together, forcing all other parts of the legend to be the same.
The air forces part can go but the impact of holding each aircraft would have to go underneath each aircraft. This would not look as nice IMO.
The sea forces part as you can see is with the biggest part of the text. This would then look stupid as you have the bonus part followed by a lot of text which no one will then read. Not sure if they will now.
To add the extra space so a couple of images of dials can be added seems pointless considering they would not add to the GP in any way. What would happen is the legend would become less functional, look squashed and have a feel of an after thought about it.
I will bring the border up to the top and bottom around the navey and between the 2 land parts. This will get rid of that funny looking area and make nice neat boxes. Because of the different parts of the sea and land being split up, I will change the text colour for the 3 area so it can be seen at a glance.