I like your quilt better than Hoffman idea. I think I would SITD every third strip of the strip sets and then do either meandering stitch or feather stitch in the black sashing but not stitch over the small blocks in the border. You might think about SITD around each block so that they would be the feature of the sashing then do the meandering or feather
Would love seeing the finished the quilt, please post another picture. Chris