Reversible Knitting

For my next shawl, I've given myself two constraints.  I have a skein of silk yarn that has subtle color changes in it.  I'm trying to work up a design that is reversible and that has horizontal lines to it so that the color changes in the yarn move with the design, not across it.  Originally, I had hoped to incorporate a fish motif, but the yarn striping has obscured my attempts so far.  Patterns with attractive reverse sides are few and far between, so i keep swatching to find the reverse not as attractive as I had hoped.  I've ripped out several swatches in this precious yarn to redo them again as I've been afraid I'll use up the skein swatching otherwise!