Quote - I would love to work with somebody who can make good control maps - not detailed feature by feature images, but rather large-scale variation in a type of feature.

Then I would use those control maps (and possibly some pattern maps) to produce a shader that is mostly procedural.

Here's an example - I made a large scale color map, with no detail, just broad strokes of different skin tones. I also made a vein pattern map. This was 15 minutes work in Photoshop starting from nothing - no brushes or anything.

Then using procedurals, I apply various forms of diffuse color variations. The freckles are from a Spots node that could easily be controlled for size and intensity using gray-scale control maps.

The overall bump is just Turbulence.

Individual medium-scale bump features like wrinkles should be drawn as independent bump maps, which I'd combine in the shader.

Small scale bump features besides the turbulence (such as pores) would be handled by a pore pattern map and a control map to show where to apply it.

These maps could be many times smaller (less pixels) than how most Poser artists do things, resulting in a net decrease of memory use.

I think this is a pretty credible skin texture. Somebody with the right tools (ZBrush, DeepPaint, Sculptris, etc.) could make seamless control and pattern maps in very little time. These are the resources you really want. Then they can be combined in lots of interesting ways in a shader.

(Click for full size)

I've been contemplating this very thing for a long time.  To have a base procedural skin material that you can add details to with various maps.  The skin material would control the skin color etc.  Could you post this material bagginsbill?  I'd love to do tests with freckle maps etc....

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