Hey Cels, lovely stuff as usual! 
There's a few things that stood out to me though, and I did a few edits:
Thanks!

And thanks for doing the edits, that's really useful. Your evil guy looks a lot more menacing than mine, and I really like what you did to those flames. You did a lot of great work to clean up the portrait. While I kind of feel the mouth is a bit too wide in your version, everything else looks really, really improved. Especially the nose, ears and the metal collar. I love how you used the yellow on the metal collar. It really tied
the room the colours together .

I had a real issue with the portrait, because it's basically based on a very stylistic drawing of a computer game character, so it's kind of like a comic book style. And when you try to do a realistic version of a comic book character, you get into the uncanny valley. The hair, for example. When I tried to do the hair in a photorealistic fashion, it just looked too creepy.
1. I feel much of the piece is pretty messy ( understandable considering the scale!) there's a fair bit of pillowshading going on.
One such place where it is most apparent is the hooded villain dude. It looks as if the glowing eyes should be light source, yet every highlight is placed in the middle. Creating a bit of banding.
Yeah, there's a lot of messy stuff. Like the ear you worked on. There's a lot of stuff, looking back at it now, where I'm thinking "Oops, did I really leave it like that?" I spent so much time on it, I got blind to those things.
Great point about the pillowshading on the hooded villain.
2. The whole piece seems kind of clean and calm for a war zone, that might be a wholly stylistic choice though. I added some life to the fire, intertwined the flames with the smoke a bit, made the pillar a bit irregular.I would consider maybe adding a couple of gray-ish shades to dirty up the scene a bit, add some details and texture to the ground. Overall I like you palette a lot! reminds me of Mykola's stuff http://www.pixeljoint.com/p/6661.htm
Yes, I did try to keep it clean and calm. Actually, it was supposed to all look cleaner than this, because that's an important feature of this style. As you see in
this music video. I love that look, but I had to compromise because I also love the techy and dirty look of Cyberpunk / Bladerunner.
Some good critique there though and thanks for the link. He does have a lot of good stuff.

3. I think the pillowy and blobby shading rears it's head at the portrait again, don't be afraid of angles and creating shapes with contrast, especially when the rest of the piece is all about angles! I don't think the yellow works in the face, it burns a bit compared to the other colors. Places like the ear look pretty rough, plenty of space for cluster optimization there! I also tried merging the colors a bit to get some unity and some of the aforementioned grittyness into the frame.
This is a very cool piece, I have a similar love for that eighties sci-fi aesthetics!
Also I LOVE! the logo that is very beautiful and clever!
Thanks a lot! I will take another look at the face, using the feedback you gave me. Much appreciated!