Put some work on nose bridge, mouth and chick. You can use anatomy references to nail the forms. Also look like some of hairs are penetrating in the head.
@sacboi, I appreciate it, but I wouldn't be able to get as far as I did without knowing these :) I'm mainly working on a simplified version of this mesh and use DataTransfer from it (haven't done any fixes on the final weight-painting yet). The problem is not in tools themselves (as far as I can tell), but more... basic -…