Be Brutal.

'Tis blackness!!

It's very good for a one-coloured avatar ^^

Only thing I would reconsider is the red string on the Balloon, and perhaps a different hairstyle to make it easier to see the "I am a person" shape XD

Very good looking Single Colour Avatar
I agree the rest string from the balloon seems out of place... unless you add a bit more red detail I would remove the balloon

I think you should get a different hairstyle as well. Maybe add some more red into the mix. Maybe make the hair a dark crimson color if they have it. That way things balance out a bit more.

Uhm, not realy good, in my opinion, way too much black.