For the colors the main issue is it's a mostly monochrome sprite and pretty desaturated. Even if you want the sprite to have a plain palette overall you could try adding in a brighter color for one or another parts of the sprite such as the feet, beak, etc. If you're having trouble with colors...
Expertise: I do pixel work, primarily Pokemon-style fakemon sprites and tiles. I have limited/basic experience with trainer sprites and various other Pokemon-style sprites. I don't do overworld sprites.
Examples of Work: https://www.deviantart.com/magiscarf/
Method of Contact: DM me or reply...