Here’s a Kal Penn caricature by Dominique that really gets a couple of things right.

It’s hard to be aware of a subject’s eye spacing.  Most of the caricature artists I’ve seen (including myself) start with the eyes, which kind of locks them in early.  If you haven’t observed immediately that the subject’s eyes are close together, you’re likely to finish the drawing without including that detail.  It’s an important one.  Eyes that are close together or far apart are integral to a likeness.  So the close-set eyes here really help to convey Kal Penn’s unique expression.

The other great thing here is the lower lip.  That’s a more obvious element to exaggerate, but it’s still cool.