Pinkie Pie: Extroverted. Pretty idealistic: she wants everyone to be happy and will sometimes go to extreme lengths to make someone happy (esp. in the case of Cranky). Slight Asperger's Syndrome (sometimes she cannot read social cues, takes things literally, difficulty remaining seated and still [shared trait between Asperger's and ADHD so it doesn't mean she has ADHD].) Major sweet tooth. One of the happiest ,if not THE happiest, being in Equestria. Slightly psychic (pinkie sense, wild guesses being totally correct [Equestria Girls]). Funny and quirky.
I wouldn't say she's obsessed with heroism. She actually IS heroic but also loves to be praised and heroic acts are one of the things she does to get praised (Mare Do Well and at the Gala). What she mostly is is insecure. She never wants to seem "uncool" and avoids certain activities such as going to the spa or reading just so she can keep face.