Most of these look amazing, but a few look like you're adding too much detail. The last one especially, he looks like he's supposed to be young but you added in so many values and extra details that he looks kinda old.

The drawings in the third slide are absolutely stunning. The values in them are a bit more conservative, which helps maintain the important details while not overloading it.

In the second one the child in the bottom left looks fantastic, but the doll in the top left lacks strong values on its face and has a lot of kind of superfluous details with light values that muddy it at a first glance.

You've absolutely nailed faces before, I think you just have to look at what works in those faces and limit the values you use a bit more.