I like the snow version more, even though it does look pretty repetitive. For the displacements on the top, yeah, the bottom and sides disappear, but theres an easy way around that. Just copy the brush you want a displacement on, and paste it next to the original. Then make the top a displacement, and raise up the middle so it sticks up. Then move the displacement to the same place as the original brush that you want it on top of, and wala, now theres snow or whatever on top of the original.
I dont like that brown wall on the edge of the map though. Get rid of that, and make it like a simple split rail fence or barbed wire or something, and make hills in the background. Otherwise it feels like you're trapped inside some little cube with a bunch of barn like buildings in it. You have to create a good atmosphere and mood too, and the easy way to do this is with stuff in the background and sounds.