Based on On My Avatar...

[PoisonXLilly]

What Sailor would I be? heart  

[Half Hero]

Sailor Neptune whee  

[NorthEastFire]

I'm going to say Sailor Neptune, too.

The hair color isn't exactly what I would imagine for her, but it seems most common for people to give her black hair when they're drawing or imagining the characters as real people, so it could work. The style looks more like hers than any of the other characters', and the eyes are the same color as hers.

You also look a little like Mars with slightly shorter hair or Saturn with slightly longer hair, if you changed the eye color.