The two quilts you are looking at are really pretty, but I'm not sure where the ombre comes in. The two quilts you shared links to look like careful placement of blender fabric, where the color is consistent thru the whole piece of fabric, and many different fabrics were used, not ombre. Were you planning on cutting squares rather than strips and letting the ombre work as the strips? That would work for the rail fence, but not the log cabin. I guess I'm just confused. Or maybe I haven't had enough coffee, probably both...