the neck area is a bit hard to read for me but the face (textures and all) is spot on. 

nice

Can't see the ref.

Ah hey, Tracer! Nice choice, even though Mercy best girl ;) (haha, I've never played TF2 or anything similar, but I like Blizz's take on mobas with HotS, so we'll see!)

I like the clusters you've used on her face and hair, makes her look very sleek and digital. I might extend the shadow on the neck to round it out some, just because as it is right now it looks kinda stiff and non-organic, even with the style you seem to be going for.

Also, you got her eyes down, but she doesn't seem cocky enough - I think just a little smirk would do it. Super cool avatar though!