To avoid the repeat of the wood grain pattern, a larger and filtered path was clipped to the rectangles and for the "cleaner" structure used cloning.
However cloning and group transformations messes up the whole thing, you cannot move the parent objects nor delete them with keeping this tiling pattern intact. What a bummer.
Also snapping to clip path nodes is not possible so it was a bit complicated to stitch together the pieces.
At least the result looks quite decent for an svg. (Made with inkscape)
svg source 1
svg source 2
Edit: adding a new variant made with the filter pack of the following post.
svg source 3