Power Pack debuted in 1984. I was nine, and so I was certainly the target audience for a comic book about a group of elementary school aged children with super powers. The four Power siblings - Alex, Julie, Jack and Katie - saved a dying alien fleeing his enemies, and in return he granted them a variety of abilities that would help them protect their family and the world from the impending menace of the rapacious Snarks. It wasn't complicated or particularly heady stuff. but the idea of a group of children as superheroes without adult supervision was groundbreaking. What made the series work for me was the dynamic between the siblings, who would bicker and whine and yet clearly love one another and take care of each other. They confronted evil aliens and super villains, but also struggled with real-world issues such as drug abuse, homelessness, and sexual abuse.
Alex was the eldest brother, and assumed that put him in charge. Jack was the resident hothead and Hawkeye to Alex's Captain America, while Katie was the little girl, the reckless enfant terrible. In the middle was Julie, the Susan Pevensie of the group (I've always been struck by the overt parallels between the Power Pack kids and the Narnia gang - the children mirrored in age and distribution). Gentle, thoughtful, mature, a voracious reader, Julie was the caretaker of the group, and while reluctant to resort to violence, she proved a doughty enough combatant at need. Her power was super-swift flight, hence the moniker Lightspeed. She always struck me as the most real of the four, the least embedded in caricature or consumed by their new reality. She thought in terms of consequences, rare enough for a 10-11 year old, had a swift strategic mind, and was probably a better natural leader than her older brother Alex.
Power Pack only lasted about six years, but was worthwhile reading as the family/team encountered and developed friendships with Wolverine, Spider-Man, and Cloak and Dagger. My own eldest has found my old copies and devoured them. The Powers have turned up in later iterations, and apparently now Lightspeed is at Avengers Academy, continuing to develop her powers and working through her sexual identity. I guess everybody grows up eventually, even in the comics.