I understand the reason you used the blue gray for his beard. Right now at 100%, it looks like a big gray blue shape with a small eye mask of skin tone on it. The blue all melds together, especially since you use the same dark shades for the beard/robe border on the robe's wrinkles. Breaking up the large, single ramp region will create more visual interest than it has now. The gun just isn't enough, since as humans, we put a priority on the recognizability of a face. This appears to be a game sprite, so the readability is more important than a design.
For example, say I drew a lumberjack sprite for a game, and I pixelled a plaid shirt on him. Now the shirt helps the player understand the character, but the plaid itself might look too detailed and confusing at that scale. In this case, it would be necessary to abandon that design, choosing a simplified alternative. The plaid could be added in the portrait or close-up cutscene picture along with other details. Does this help clarify?
