Homespun is very popular for rag quilts because it ravels nicely. I don't think batiks would work well (though I could be wrong about that) because of their tight weave. I've used flannel and corduroy, have seen them with homespun and "regular" quilting cotton. I've also seen them done with fleece - no raveling, but the curling gives a different look. I don't use batting (3 layers of fabric instead), so there's no need for any quilting and all layers can be cut the same size.