This is three pitches in one, with my personal opinions in a post to follow. Please add yours if you have them.
Recruit Teenagers With Attitude
This is option 1 - just run a new game, and instead of capturing lightning in a bottle, create some new lightning.
Masks II: Son of Masks
This is option 3, above. Move the timeline into the future about 20 years to allow for it, so it’s now about 2040. The Menagerie and other teams now occupy the spot the HHL held, but there’s new challenges and new bad guys, that means new heroes.
This is kind of a combination of options 2 and 4. The game is set in a Halcyon City with many familiar elements, buuuut with some key diversion that means the Menagerie never formed as such. Maybe the team’s members solved their own problems a different way, or maybe they didn’t come back from some key mission because they decided to do something else, or anything else you like.