This glowing review of The Unbeatable Squirrel Girl highlights some of the traits that make it delightful.
“The book is improbably, unflappably confident in its own voice, going so far as to fold in cheeky marginalia […] that extends gags as the action moves on. There’s no self-loathing in the Squirrel Girl character and series. You get the sense that Doreen Green is doing exactly what she wants, exactly what she’s supposed to be doing. She was born like this. Yes, she’s a mutant, but it’s more that she’s unburdened by that psychological baggage that became a prerequisite for metahuman altruism. You don’t have to have had something bad happen to you to want to help others. You can just want to help other people, even if it’s by talking to them.
Squirrel Girl’s secret power is the ability to get people to listen to and, then, like her. Considering that violence is the default mode of interaction in superhero comics, that’s an important distinction. The talk therapy doesn’t always work, though, in which case she’ll command a squirrel to shove itself inside a bad guy’s mouth.”