I've gave it a go on a bust maquette once. I've hit the same nails as you do; It's somewhat difficult to translate the anime art, with all its deformations, to real-life without losing the Beyond feel.
So, here's my two cents, based on your pics :
-The cowl must be completed by another piece on the mouth, so you have to blend it around the mouth with very thin edges. Lips are not that present. Please try to look for info on special make-up with multiple parts to see how they articulate pieces together.
-The white eyes lenses are smaller, like Oakley lenses without the glasses frames. I know they sometimes appear bigger, but that doesn't really work.
- The ears change size from time to time. They start from the cheekbones and are going up, but they also staying close from the head's width. If you have trouble sculpting because of their own weight, I suggest to use a metal wire mesh and bend it like an elongated pyramid.
- The cheeks and cheekbones have a distinct groove, too high on the face to be realistic. Still, you have to make them appear. Same for the nasolabial fold, which must end on the upper lip corner.
Good luck with your sculpt, looking forward your updates.