Marvel's Guardians of the Galaxy

This continued story of the ragtag group of former criminals turned unlikely heroes plays to a younger audience than its parent movie does, thanks to generally more kid-friendly content. There's still a lot of violence, but there's also less death, and its animated format takes the edge off the exchanges that exist. Thanos remains an intimidating adversary, to be sure, but he and the other bad guys are less threatening in cartoon form than they are in live-action.

What sells the Guardians as protagonists is their relatability as individual characters. They're imperfect, they can be rash, and they have complex backstories that influence their actions and evolve as the series progresses. This makes them intriguing standalone characters and affects the group dynamic in interesting ways. Lighter moments can be humorous, and there are some melancholy ones that reference Peter's family's past. There's also a definite advantage to having seen the movie and thus knowing how the characters came to be a group, but newcomers will get up to speed fairly quickly.