Yes, I suppose they are. They're common collocations, so we don't often think about whether or not they are literal. Both could be seen as images. 'Unruly hair' is a kind of personification. 'Unruly' means disobedient or difficult to control - like a teacher struggling to control an unruly class. If you describe your hair as unruly, this means that it refuses to 'behave' like you want it to do. 'Piercing eyes' is a different kind of image. This means that the eyes look at you so directly that you feel as if they're forcing their way into you, like sharp needles.

Of course they are