Nice work man. The sheen on the metal is really nice (it seems like you've also applied a bit of a mat ish surface to the left wing which looks nice. The colours complement each other well. And if I may add, has a very Dutvutian feel to it with the excess amount of spikes as well as the theme sci-fi. If you haven't seen Dutvutans work I would definitely check him out. But yeh, I do find the angle of it weird. The legs are positioned making it look like we should see the front more, but the head/front LED thing of the robot is only barely visible, making it look... No offence... Awkward... I feel like it's mostly the front right leg that kinda destroys the illusion however I think the only correction if you were to do any (not that you should buuut) would be moving that leg a bit closer to the frong left leg... If that makes sense... Also, I feel like you should experiment with poses, even though I know this is only concept art and you're only wanting to show of it's size and general look. I feel like a pose could be a very good way of expressing it's function in more depth and depending on whether it's got some sentient, self aware AI... It's personality...
Also It seems like there are conflicting lighting effects. The shine on the front left leg makes it seem like it's hitting the metal at an angle smaller than what the shadow makes it out to be. However, the light hitting the left wing makes the light look like it's right above it, although It's not very noticeable. However, I might just be me being wrong about how light works so please if you want tell me I'm a fucking idiot... I feel like that sentence is also structured wrongly... Hmm...
Anyway, I'd like to see some more of this stuff in the future (/^v^)/~!