Well I've thought about this before, it just seems reasonable that if you can tell if hangars are up remotely, you should be able to tell the status of the town. But what's worse about the town is a a lot of the time you have to get in a vehicle and fly/drive to the town yourself to observe it's status. That's not necessary with the fields because you can see its status in the clipboard, on the chalkboard in the tower, and you can visually see the entire field from the tower.
You would think with how important towns are to the capture of fields that there would be SOME way to keep track of it. When talking about realism if the field is able to relay all sorts of information about itself to you while you're in the air it should be able to tell you SOMETHING about the town seeing as a majority of fields have a line of sight to their towns from the tower, and to the think the town defenses aren't in any communication with the defenses at the field regardless is silly.
+1, and instead of color codes how about really tiny health bars? Or maybe the flashing of the icons can become increasingly faster as the state of the town becomes more urgent?
(Got ninja'd by 8 guys, posting anyway and will edit if needed)