Great lines, expressions and gesture. Right now I'm going through the Loomis book that Proko uses to teach heads. I'm seeing a lot of proportions that are not lining up properly. It's very important to Loomis that the initial proportions are correct. For instance your ears are above the brow line when they should be even with it. There are also some shapes on your faces that look "2D" as in you put in a 2D shape instead of thinking about how the form would look in perspective. But really good work overall!

I think your Reilly head looks great, I think when you stared to apply shading it's kinda falling apart. Think about the direction of your light and use the guides you created as plane faces.

These are looking great! Looks like you're making the spinalis and erector spinae way to prominent. They'll soften when they get to the mid part of the back and they are smaller then they appear in the lower back, so I would revisit the proportions.