Psyche isn't bad, but, like others have mentioned, close to Psycho.
However, I love Echo! Short two syllable names really appel to me, as do mythological names. And I really like the sound of it. If I ever were to use it, I'd consider it as a first name, but probably only use it as a middle name.
Julia Keelan
"I don't mean to be rude-" he began in a tone that threatened rudeness in every syllable.
"-yet, sadly, accidental rudeness occurs alarmingly often."
~ From Harry Potter and The Half Blood Prince by J.K. Rowling. Vernon Dursley to Albus Dumbledore.