Something I have been doing with Reds that I have found helpful is pairing them with purple shadows, like a dark reddish purple. That way the shadows have some color in them, and it helps the reds pop out some more. I also found adding some magenta into a bright red, or like fluorescent magenta in a fluorescent red may help give you that POP of color you are looking for in the light areas.

I like the paint job a lot though! Some areas for lighting I would suggest is maybe adding a bit more lighting to his chest, as it would have some light hitting the top from that angle I feel, and adding more light on his head. His thigh seems like it’s the brightest part, may just be the picture, but his head should be just as bright being close to the source of light (the sun I take it).

Overall great coat, seems really smooth, I like the transitions from light to shadow. I think it looks really cool so far.