Fuck yeah, congrats on the progress!
If you're interested in photorealistic portraits, I recommend learning face geometry! It's a super helpful starting point, and once you have a sense for it you can look at a face and see how it compares to the norm, which helps you recreate what makes it unique. Or if you're drawing fictional faces, give each face defining structural characteristics that give them their own distinct feel
In these examples, your eyes look a little bit too high, and the forehead a little bit too small, which is an extraordinarily common mistake (assuming it's not what you're going for, in which case it wouldn't be a mistake). The eyes actually sit at about halfway up/down the face, which intuitively feels way too low, so many folks place them a bit high.
That might be a intentional stylistic choice though, but even if you're going for something stylized it can be helpful to know realism :)
These look fantastic! Sorry if this was advice that had already been given, I didn't see the original thread. Keep up the great work! ❤️