Japanese Town center farm enhance aura

I think it would be quite a good idea to put a glowing effect when they are within the aura of the TC with the upgrade, like HRE or RUS villagers for example. Although you can still obviously see the large aura and tell if they have the enhancement or not, the farms on the corners that the aura only cover half of it, cannot be easily determined if they are having the enhancement. They reason these farms are built in corners is because in cases where you need to built them behind base due to being rushed by other civs.
Either that or you can just do what the English does with their farms.