In my personal interpretation of the Bible's creation myth, Eve's sin was to connect with her own womanhood.
It was biting the forbidden fruit of owning her feminine essence as it is, the connection between spirit and flesh. The decision to embrace the sacred of giving life, pleasure, protection, and love. Amazed by her discovery, she decided to share. Share the love and wonder of self awareness, share the "forbidden fruit" with the world. And thus she shared and by sharing she was punished.
For me, Eve is no different than Prometheus, angering Zeus in order to give fire to mankind. We are all Eve, Adams, serpents and gods. We just shuffle between archetypes, putting together our own version of Eden. I see Eve not as a gullible woman who let herself be fooled by a serpent and by this was punished.
I see Eve as the one who questioned paradise and wanted more. Wanted to know more, to live more, to experience more. Her sin was being brave enough to give that first bite into the unknown, and dare to be closer to God and become more than just their image.