A modder has made what I think is the most loreful reskin of CA's Necrarch Lord using existing assets:
The author took inspiration from the following official Necrarch art:
A few more pictures:You can find the mod here.
I think this reskin is so good, CA should just incorporate it into the main game, or at least put a bit more effort into the current Necrarch. The only thing that is really missing here for it to be closer to the artwork is longer fingers and claws, and longer, more pointed ears. However, those are things only CA can fix at the moment.