So I started coloring and shading this drawing, but something seems off to me. Any suggestions?
Really? Do you think you could find me an example of what you mean?The brush you are using to shade is too soft. Where it goes from light to dark is blended together too much. It doesn't have the feel of something hard and metallic.
But will give this a try and see how it looks, for sure.Not really. It's about the brush. You're using a basically airbrush, a brush with 0% hardness. Increase the hardness to at least 70% or even 95% and it will give you a much better effect. Or use other brushes. Mixing brushes is always great, but an airbrush is very no-go for mechanical things like that.