"Elemental" & "Racing Green" color schemes look good for me. "Void" series is too contrasting, maybe something similar, but more dimmed?
I just took the screenshot of the (brown) Nocturne skin and used Photoshop to turn it into greyscale to see what a grey version would look like.
I'm not sure about it, perhaps a little bit boring?:
yes, it's really boring. but i didn't mean completely grayscale version, and referenced 'Elemental' skin is not completely grayscale too. interesting how it would look if you add colors to some elements and maybe some subtle saturation to entire skin.
p.s. presonally i very like some variations of these 2 colors:
saturated orange
and not too saturated blue
EDIT:
also, 'orange' and 'not saturated blue' usually look great in combination with black and white (or very dark and very light) colors respectively. 2 examples (but they are only examples):