Well if your planning to make a "Wall" for a FOB-ish kind of feel, to make a long wall you could construct a "Frame" to the length of your "Wall" with Wood, then surround the outside with Chicken Wire, then place the landscaping fabric of the same length of the Wall in the middle of the "Frame" and fill with sand, dirt, bodies of your eneimes ETC. then to top it off, place another layer of landscaping fabric over top of the Wall to Cover.
the Filling Ability will accomplish two of your objectives, the Weight Down and the Fill Part, as the Dirt/Sand will be able to do both at once.
But then again this does take some work, but it would be more stable.
Sorry, just tossing out ideas