I love Andromeda! It's such a strong, striking name, but it still feels familiar and, oddly enough, somewhat down to earth. I think Andromeda Faye is perfect, and Faye is the right balance of more common, but with a good deal of magic and whimsy in there by definition. Plus Faye isn't the most overused filler imo, so it's somewhat unexpected. For nns I don't think you can completely guarantee Andie won't crop upp, but you could use some others to introduce more options. My favourite is Ro, but there's Rom/Romy, Meda, Edie, Eda (Ee-da), Emmy, Demi, Anna/Anne/Annie, Daffy or Effie (with Faye).
Dreaming of...
Pandora Beatrix Fae ✦ Caspian Sherlock Walter ✦ Artemis Valkyrie Clio ✦ Lysander Atticus George
Ptolemy ✦ Horatio ✦ Nikolai ✦ Ambrose ✦ Zephram ✦ Indigo ✦ Cedric
Evanthe ✦ Morgana ✦ Zenobia ✦ Marigold ✦ Lavender ✦ Demelza ✦ Calista