too much: lower right curve of the big tooth on the right. elsewhere as well, but mainly I consider that a banding problem. too little: the black lines between the teeth, the outer contours of the teeth. tilting towards a color: tinting the grey. making it a slightly reddish grey, or bluish grey, rather than a grey grey.

Thanks for the critique. Could you be a bit more specific, though? I'm wondering about: 1) where I use AA too much/little and 2) what you mean by tilting towards a color? Like I said, kinda new to this.

aa is too thick in some places, completely absent in others. banding occurs on the teeth. when using greys, it's often better to tilt them towards a color, so that they're not completely desaturated and lifeless. this tutorial explains aa and banding if you need.