Light: Special note to the light, which heavenly depends on the existence of a background or not. If there is none, like transparent or flat colour, then there is a 50/50 chance I may add some random light source to make the drawing pop a bit more. Be it natural light, cold or some neon light if it adds some spice to the character. Sometimes it might be just a colorful outline. If you want the art piece to mostly maintain the original colours, you better voice this before, since usually I tend to play with the colours just a bit. Backgrounds with a Scene, usually decide the light for me, like in a forest there might be some sunlight, shadows, the leafes green reflecting on the character, etc.
ADDITIONAL INFO
What's the difference to Icons? They are basically a bust, so you see more chest and full face, so no horns or ears getting cut off by the limit of the bg. Standard is the neck ending pointy as in the examples, head floating. But if wished, the rest of the neck can be drawn till to the edges of the canvas, which is guaranteed by a detailed background.