Actually, the Goths almost never lose against Siege Weapon/Archery civilizations, like the Maya, or Britons. Yeah, put them against the Huns, and you are just plain screwed. The Goths are like the Zerg. Tech their Uniques, and pump them out as fast as you can. A nice Castle Age rush puts many players to sleep.
I'll admit, it's been awhile since I played, but I don't use walls at all.