Both of you are right!
It should be a mixture of both styles as it needs a slight second lightsource which would happen to be the purple one, Helm's is too Marvel'ish
You're heading in the right way EvilEye, and this would turn out to be a good tutorial I think...
To your first post, and to discuss a little...
A piece like this would take 2-3 hours for me because of some reasons
I don't bother with lineart as I draw with areas, you somewhat did the same by starting with black but that was it
and you're already bothering with having the lineart clean, which should be only touchups in the end result (saves work)
also, don't always concentrate on parts of the reference, think by yourself!
Anatomy skills help LOADS if you do something like this
as Helm said, you're indecided about the actual process!
Now a comment to the actual image:
Looks nice!

As for backgrounds to pixel on, I prefer magenta
