We really like your concept, and are undecided whether we like the white or black background better. We think the white background is easier to see, and the contrast seems cleaner to us.
We also like the angle of the graphic in the head; it seems progressive and powerful.
One thing we'd like you to consider is somehow modifying the full head and neck graphic. The stem of the neck makes us think of a manequin, and this detracts from the overall image. At the same time, simply cutting off the neck wouldn't look right either.
Maybe you can take our thoughts and incorporate them into your vision.
Thanks for the work and ideas so far. We like where you are heading (no pun intended!)