i love the Fallout trapps, bear trapps, rigged shootgun, grenade bouqet etc
other way to defend to etc improved barricade - stronger or maby add sharpned poles to it so you get damage when running in to it or trying to climb/jump over it.
landmines, alarm system (noise and light)
maby option to get guard dog or something thats in a hidden cage that be relesed when coming to close or stepping on tripp wire.
I think metal walls will also bring metal barricades. If metal barricades would be possible, I think they would have different names