This is a WIP of the concept art from a project we are working on. Please give me some feedback 
It is about an ex-gangster who has an accident and he is reconstructed with bionic parts, unfortunately the medical intervention drained all his emotions. He then uses his intelligence from the brain implant to recover each one of his emotions by killing people.
Cheers from Barcelona,
Alan Monroig
It looks more like an illustration than concept art. How is this image used in the project? As pre-production concept art? Promotional illustration for marketing?
Why is his cyborg arm exposed like that? Is it on purpose or his sleeve was ripped off?
His pose looks a bit awkward, with his right leg raised at unnatural height and the wrinkles of his pants at the thigh area looking incorrect. His arms also look a bit too short for his body’s length.
The composition isn’t ideal, since you have him overlapping the skyscrapers in the background. The cityscape is meant to convey the premise and create a sense of place, but also provide support in the composition, so it’s best if you don’t overlap/block it like that. The better approach is to offset them so they create a counterbalance to each other. You also have a lot of useless negative space in the image that does not benefit the narrative or the composition.
If you have never studied composition, I suggest you do some research and look at the main guidelines that help with creating a more interesting and pleasing composition.