Thats looking good to me, its depends where you will use them on. For example: in a realistic propose will not fit, but in a stylized scene, that will fits very well :)
Good anatomy. Everything seems in good realistic proportion. There are some edge loops in the jaw and face that could be smoothed out, but the volume is looking pretty perfect.
first of all. What kind of junior character artist? Stylised? Realistic? xD Search for Junior portfolios on Artstation. See what they do and what they use.