Judging by how it looks in b/w, I think you're totally nailing the background.
Considering how dark the barrels are, his face and chest might be too bright, depending on how realistic you want to be. Given style you have, I'd say it's totally fine to push things and have him be more illuminated than normal.
In case you have the time, darkening him and giving him some more expressive backlighting effects around his mane/hair, could increase the overall intensity of the image. A good reference is Michael Malm and how he give backlit hair and almost fire-y look.
It's such a fun piece though, so I look forward to seeing it finished!
You're in the home stretch now. You got this!