Choosing a POV for a given project is quite difficult.
When my protagonist is a teenager, I tend to use the 1st person. Teen protagonists are usually read by teens, so the first person POV allows the reader to become intimately involved with the thoughts and emotions of the character. Teens also have a million thoughts in their head, so the 1st person narration allows that jumbled mess of ideas to be displayed on the page.
When my character is younger, or when I'm telling a historical story, I like the 3rd person POV. Younger readers don't care as much about the inner workings of the mind, and young characters shouldn't really be able to articulate themselves that well anyway. The 3rd person helps maintain that distance. When I read a Middle Grade story with 1st person narration, I'm usually negatively distracted by all of the details. For me, it's just not believable that a 10-12 year-old would have such a firm grasp on their thoughts and emotions.
It's raining. Time to curl up with the cats and read!