Here my opinion :
The main symbol of the puppeteer is that wood cross on which the strings are attached:
http://www.istockphoto.com/file_closeup/?id=14803377&refnum=1647260&source=sxchu04&source=sxchu04
but i don't know where you could find a stock with that. If you do, it would improve the mood for sure.
You have 3 girls, all in white & all brunettes, which lowers the impact, cause of the same element repetition ( and not cause they're brunettes ) .
You could:
- either keep just one, controlled by two hands = more of a "being controlled" feeling.
-or have them all in different colors, neutral color on the foreground girl, & opposing colors on the other two.
- or one evil one good, one sad one happy, etc.
That would give a "playing with your mind feeling"

....master of puppets is pulling your strings
twisting your mind, smashing your dreams .... as the song i think it should have a darker feel, but that's just me

I have to agree with gornats, when I listed to this song i don't get a mental image of pretty ballerina girls.

Gornats: The song is about drug addiction. Hence I can see why people couldn't get the ballerinas, as opposed to drug addicts.

That's what I see when I'm on drugs; just wish I could see the strings maybe go around the fingers... Still like it!