nice idea for a model

Do you need the extra geometry that makes a cut in his collar as this could be textured to give the impression? (bottom left pic). The ear also looks to have a wasted little tri/funny geometry.

Do you need so many rings around the next area (top right pic) and could you simplify the number of quads on the back area? If the back is quite flat then maybe a simplified reworking will knock the poly count down.

I'm no expert but they just jumped out at me as possible optimisation areas

Si