Thank you for giving us so many designs to consider. We are really looking for a symbol that has depth in its dimensions. I think that #34 and #20 have the most potential, but they need to be made more striking. Maybe if #34 was simplified a small bit and given a deeper dimension it could work, or work on that particular design idea and push it to evolve further.
#20 the same theory applies, we would like to see it pushed further and given more depth.
The colours dont really appeal. In any of the designs you have gone for very simple colours. Sometimes a broght splash of colour gives a design more of an edge.