A little note about something I come across from time to time while editing. Do not switch the point-of-view just to get something across to the reader about your protagonist, particularly a physical description of him or his actions. It’s a cheap writer’s trick, it’s lazy, it’s unnecessary, and it breaks up the flow of the story. Moreover, you’re not fooling anyone about what you’re doing or why you’re doing it.
There are many good reasons to switch perspective. Doing so in order to make a Mary Sue point about how handsome or determined or pretty the protagonist looks is not one of them.
On the other hand, never force heavily self-descriptive adjectives into the protagonist’s internal monologue either. It makes the character sound self-absorbed and sociopathic, rather like a highly intelligent and impressively well-read man with muscles like a well-honed panther referring to himself in the third person, wrote Vox Day.