Digital Painting - Sirens

I'm going to have two paintings in a gallery show called "Femme Fatale". This is a color study I did for the solo painting I'm submitting. The painting itself will be in watercolor and guoache, whereas this unfinished color study was done in Adobe Photoshop.

I'm working on the final painting and it's really exiting, but I still haven't decided what color the sirens should be. Does anyone think some kind of purple would look better?

Gallery piece - Sirens

The idea behind this work is the stories surrounding the sirens of myth. These bird-women would seduce sailors with an intoxicating song, then murder the people drawn to them by the song.

This is a test run for the underpainting. I'm trying to establish the lights and darks, and I hope to achieve a good balance of light and dark. I am going to paint this and submit it to a gallery show themed "Femme-Fatale".