well you asked for advise and thats what I'll give you but I do have alot and I hate to type so here is some of the bigger problems.. keep in mind I am a very picky person ^^... I can see a very clear seem where you mirrored the face you should go over that with a patch tool, ad some brighter highlights around the eyes chin and nose, the eyes are dead looking you shout ad some fake reflections to them and maybe make them a little higher in contrast, the eyebrows look painted on and I would need to see the body alot better to give you any advice on that.

    please keep in mind I am trying to help I mean no disrespect ^^
       It looks very nice from what I can see I am just very picky