Any photoshop gurus here?

[Alex]

The source of you're problems is that you're using a photograph as a drawing and trying to get the properties of the latter from the former. This will almost always require a lot of grunt work and cleanup since you can never really get the sharp delineations in a photograph that you automatically have in a drawing.

If you have anything approaching the artistic ability I would simply redraw the image from scratch. This is how the graphic designers I used to work with would always start if we wanted them to use something from a photograph in a non-photorealistic way.