Try to make a specular map so different parts seem to have different materials. Right now the tusks look as if they are made from the same material than the skin. If you can break that up, it will look much more life like.
Usually I am not a big fan of lens flares. But I think they look good with the volumetric light. Maybe you can make him a tiny bit of fog-breath. just a bit. Like a t a cold morning. The falling leaves would fit with an autumn morning.
Just a few ideas…
Cheers
Lemo