Okay.
- Use more colors/shades of colors/color scheme
Using more colors or shades of colors can be really useful to send out an overall vibe. Maybe you could use a few yellows to compliment the blues, but don't add to many or oversaturate them. Usually a good color scheme has around 3 colors or if you're going monochrome really differentiate the shades.
- Use a more expressive pose or face
Using emotion and body language to contribute to a character is a crucial part of the process of making an oc. Some really good poses are in the "extra" section. With faces, the eyebrows and mouth really could amp up this guy. I don't get the feeling of interest I usually get around OCs, because he's not very expressive in this scene. Remember not to go super extreme though, and stay reasonable to their mood.
This is a really good Oc nonetheless, I just wanted to give some pointers.
