Your design #57 looks very refined--really like the classy look, and the conservative colors. What were you trying to convey with the blue and green dotted patterns? #56 looks more like a back than the others, but they all have great colors and attractive fonts.
#57 was an attempt at a more abstract back pattern. Though it may be too tilted, looking at it now, I'll try to think of something more along the lines of #57 but with more obvious back imagery before the contest ends :)
Thank you for your latest submission. I think it is better being vertical, but I worry that people will see this more as treble clef and not so much as a back or spine. Can you humanize it slightly to reduce this ambiguity?