The character is mo-capped, you can't really maintain that consistency (which tbh, which I'm not sure existed to begin with) if you want to minimise jank in the character's facial animations.
Lara has always been a weirdly uncanny valley character who existed in the coming of 3D graphics but is less realistic than say, Cloud and other Final Fantasy characters who actually have 2D renderings with realistic proportions. Just her face is sort of oval and unreal.
I think actually using cell shading could suit her rather well. Similar to how it is done in recent Zelda games. The "unreal" look comes from combining her simple face with realistic lighting of a normal render.
