General art critique

From my perspective, the character overall is really solid. It has great color usages, dynamic pose, stylized and unifies well. There is one thing I feel you really didn't pay attention to, which in my opinion, is the overall presentation of the character.

What do I mean with presentation?
The background and typography doesn't work with the character. It feels you just have slapped the character on whatever background you can find and then put whatever typography on it.

A. Some examples of packaging the character **

https://www.artstation.com/artwork/9RZvy
https://www.artstation.com/artwork/KPl9X
https://www.artstation.com/artwork/6NzEV
https://www.artstation.com/artwork/Lx5R5
https://www.artstation.com/artwork/r00JJ

To sum it up, the overall character has the umph feeling , but the presentation is not there. You can check more about this by seeing how designers presents their work, and also of course researching more about general basics of Graphic Design.

Wow. That is some amazing work. I agree that the background does not do that incredible Junkrat justice.

The text is good though, as its tied in with the overwatch theme, being the actual text.
Definitely work on that background. Something more simple would make him pop more.

So cool

Amazing piece man, Really great pose and colors usage, but I think that you cold desaturate some of the greens and yellows.
About the background In my opinion if you change it for something less datailed or blurred the character would stand out a more.
Very good

The background seems a bit blurry. Also Junk Rat's body seems very block rather than smooth. He seems more like a character that's meant to be skin and bone rather than muscle and bone.

The background is a bit too much. Rather than my eyes being drawn to Junkrat's crazy face, giant gun, or even those sweet pecs, I'm stuck staring at his crotch/leg, where his pants are closest to the background explosion's centre. The contrast there is overpowering, and takes away from the lunatic Aussie.

If the entire background was more like the top portion around Junkrat's head, I think it would be a lot better.

I'm also not a fan of the smoke coming from his head. I didn't even realize it was smoke (I thought it was just more of the textured background) until I looked closely.

It's incredibly busy overall, packing detail into every inch of your character can make it quite confusing to the eye, as there is there is nowhere for it to settle. You need to have simpler, blanker areas to break up the busyness. Perhaps make the shorts a flatter area of colour, take out a few of the folds and simplify. You ideally want people to be attracted to the face, so that is where the most detail should be. I would also flip the background so the yellow is behind his head.
Also slight anatomy issues: the distance from his left elbow to his shoulder is very small when compared to the upper arm.

Overall the work is very good, you just need to know where to dial it back in places and not pack it wall to wall with detail.