Here is a pic that I found on a site. (Hot-linked.. but I'm lazy):
Back to Echo Base:
If I were Adywan (with his skills and equipment), I would add tiny red dots moving on the white lines. Let the red dots represent enemy ships and let the white lines represent the various ships' orbits and trajectories.
The concentric circles would be the blockade orbiting Hoth, with the Star Destroyers evenly distributed on them.
The curve arching out from the middle could be the transport's course. Add a green dot that slowly moves up the line from the center to the circle.
When the Star Destroyer's red dot meets the transport's course, then it is time to lower the shield and fire the Ion Cannon.
Perhaps the shield could also be represented somehow on the panel.