Funny, I didn't know the great wall of China was European (my inspiration). There's only so much you can do at the scale I'm doing it at though considering everything is made from massive blocks, and there are no slopes in Minecraft.
I did play around with the gate design but the one in the screenshots is the only one that really worked for me.
EDIT: Maybe you can come up with something in creative if you think you can do better than me?