If you're using Vallejo, there should be no reason to "dull coat" your figures after painting. Vallejo, if well mixed (shaken thoroughly and when you think you've shaken enough, shake some more) finishes dead flat. And while you could argue that crews in the summer might have a sheen on exposed skin surfaces due to sweat and grease, generaly I think your safe in that being flat as well. Especially in winter or desert conditions.
Panzer crews wore leather pants and jackets and those had about as much sheen on them as a modern motorcycle jacket. Wool uniforms read flat.
Aestheticly I think you get more out of a figure if its not painted a base black but more of a dark, very dark grey and use the black as a shadow with a lighter base for highlights. Transtions should be smoother on wool uniforms. But this is my personal aesthetic. You paint what makes you happy.
As for faces, I've seen "cold weather" faces done that have much more color and contrast and are done well. The more depth you can put into your figures, the more animated or lifelike they will appear and really be striking. A redish brown or crimson mixed into your flesh colors to shade the hollows of cheeks, neck under the eye ridge sockets, the side of the nose will give a great deal of character and depth to your faces. With highlights done in a cooler tone, you can convey wintery conditions. A figure I saw done of French Napoleonic soldiers retreating from Moscow used flesh tones with a slight blue cast to convey really cold fatigued soldiers. You have to be careful with reddening up facial colors though as they too easily start to look clownish. My suggestion would be to ease into this techniqe and err to the conservative. The pale direction you use now looks good and is a nice start to show cold.
Also a question, are the two figures to be in the same vignette/diorama/vehicle?
Mike
"Imagination is the dye that colors our lives"
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