Character WIP

[Pictomancer]

Brief background on the work. My goal's to create a dynamic fanart of a character from a cartoon I used to watch. I've been working on and off this piece since Feb. Some references used; mainly for the gesture, and of course the character design. However couldn't find key detailed/matching references such as anatomy for the pose, or how the fabric flows, etc.

I'm more or less happy with the general style between cartoon and realism of how I want to paint the character; but I'm having trouble bringing the work to a finish.

Having been working on this on and off I'm noticing tham I'm going into a pattern of painting/repainting (lost in noodling). So I've set an internal deadline for myself to consider this work finished and move on. I want to try and get as much improvement as I can into the work before said deadline.

What I'm having trouble with:
- Position and foreshortening of his right arm that's supposed to be in a pre bracer slam pose (short video of the character).
- The bending portion of his left arm.

What I'm uneasy with and could probably use some advice:
- The color composition. I'm still not sure if I'm using the "right" colors as it doesn't feel "alive" enough, or rather it feels "muddy".
- Values and form, I know I'm missing some parts in the pic where the value or form doesn't read well enough and would appreciate help in those areas.
- An impish/eager/excited grin or smile.

What I have absolutely no effin' clue with what I'm doing:
The background. I have zero experience with doing backgrounds. I've mostly done nothing but characters so some suggestions on how to make the bg more dynamic, and properly integrate it and the character would be much appreciated.

Old studies of the work to give you somewhat of an idea on what I've been trying to go for:
- Gesture/Pose studies
- Color studies(?) of chosen pose

Thanks for giving it a look and apologies for the long post. Suggestions, and paintovers are very much appreciated.