I am enjoying the idea and colors, but I agree that something like increasing the spike size could help in defining the character a bit more, the simple silhouette does just kind of look like "Guy with a Sword" right now.
I look forward to seeing more!
@PeterH thanks ^^ and yeah, that was my feeling as well. At least I'm mostly happy with the overall look and feel, so accentuating elements and some proportions to make her stand out won't really interfere too much with the illustration.
So here's a version with some bigger spikes and added smaller elements all around, tried making it completely smokey below the waist (like a ghost, but I didn't like it, I want to retain the human inside)
Starting to look really nice!! 
Ok, after a break from looking at the character, I decided I can push the shapes even more and add some more flavor elements all around. At long last I'm kind of happy with how the design and the thumbnail sillhouette look.
I'd be happy with some critiques, as I've been looking at her for too long 
(Left -old; Right - new)
And another illustration WIP:
A lot of black.
Yeah, you're right I'm planning on making it just 'dark' instead of black but I was still playing around with the design and the focal area (head and torso), general hue adjustments are next on the list. Thanks for the heads-up!
Looking awesome, my only suggestion is about the background perspective, it's too close and maybe could distract a little bit
Thank you , I'll try to push it further back with some atmospheric perspective
After a busy week - finally managed another update!
Most notably (aside from some more rendering :D), I decided to add hair sticking from under the helmet to make her a bit more 'layered' and physical. Some 'exoskeleton' pieces/mech augments were added around the waist/under her arms to go with the helmet (they need some more structure but that'll be the general direction).
Also, I changed the overall ambient hue, faded the background a bit and eliminated most of the near-black colors. I'm also thinking of getting rid of the middle belt knife, because they feel too crammed as of now.
Good idea! It will also add a breathing area.
A few posts back on "composition exploration" you were thinking about mixing two views. I feel enlarging a tad bit your canvas can solves the clogged problem as long as giving you some space to show more of his superpower.
Thanks @innocent , it does feel better when widened a bit. (Fun fact - turns out it was indeed wider in the beginning, but I must've cropped it at some point, as it had the wider sketch outside the canvas XD)
The background finally got some love and attention
Oook, so the composition changed! (a bit)
I was looking at the illustration the last couple of days and something was lacking. I liked most of it, yet I think it became lifeless compared to the first sketches. So I got ye big ol' brush and added some things! It got foggier, more crowded and even wider!
I'll try to recapture and reinforce the feeling of panic and utter defeat of the 'heroes' I think it had in the beginning. I'm still changing some smaller things (mainly effects right now) but I'll upload this just as a general direction. Bigger changes are possible as well but I'll try to keep the things I'm positively liking mostly intact.
Critiques are very welcome
honestly it looks sooo great! the helmet is very well achieved! It has fascinated me!
Maybe push the focal point a little bit to the side?
Gave it a try with content aware filling the empty space and pumped up the contrast a little
What'd you think?
Sorry for messing with your stuff 
liked it a lot
Keep at it, the changes and choices made here have been solid.
The focal point change is a pretty good idea, it would also allow for the addition of a foreground guy getting messed up too. Worth messing around with.
Thanks everyone, it means a lot! And thanks for taking the time @edenriquebq! No need to be sorry, it does raise a good point
Small wall of text:
I'll defenitely play some more with enemy placement (more in line with adding something to the left?). I was going for a good old triangle shape with the composition and thus kinda need/want the villain to be centerpiece (and have all the flow lines leading the eye to her upper body/head). If the focus moves between the characters, I feel like it would translate in a more 'even fight', which it certainly isn't Then again, I will try moving it a bit as an experiment.
And as for the content-aware filter giving out more guys (hey, Christmas is early :D) - I'd rather not place any more enemies on the right, as it might get super crowded and visually heavy, even with a stretch in the canvas.
Fun fact I was going to say, add an enemy to the left xD (or something else ?)
The details on your villain is wow ^^
Keep it up : D
Oh and talking about christmas (and new year, but I guess it depends also on some countries etc)...it will be hard to work between these days T-T
University... (Architecture is all-consuming ). Thanks for reminding me how much time has passed since the last update, the days are but a blur lately.
I'm still working on it, I hope to upload another wip (close to finished illustration) tonight or tomorrow night (I'd rather bet on tomorrow though :D)
