I personally like it how it is...no artificial barrier is visible, you're just informed when you cross it. I pretty much understand where my tribal area is just from crossing it so many times. Or we could build a wall/fence....that would be visible from a good distance. With all the Devs have on their plate at this time, I think it would be a waste of time with little benefit to actual game play. You can use a shovel to "Clear land" when you step into your area...do that around the entire perimitter and you'll see pretty much of your property.