APPLYING CONTACT SHADOWS AND HIGHLIGHTS TO YOUR TEXTURE
Treating stylised characters as if they were paintings will help ground them visually. A trick to help sell the physicality and construction of your design is by adding contact ambient occlusion. This is used by adding a slightly different hue/darker shade where two separate components meet.
This helps it look like two surfaces are touching rather than intersecting – small touches like these can really make a model look grounded. Adding further lighting information such as subtle highlights and tight shadows in cavities will push them out from the flat texture and further add depth to your piece.