I’ve been have some thoughts/thought of things I wish they did:
>Less status quo stuff. It could be like most cartoons with continuation which more episodic episodes are sandwiched in between episode that advance the show’s overall plot.
>Give some depth and development to some of the side characters instead of having them be there to advance the plot for the main characters.
>Utilize the extra heroes better. Have them use their Miraculous more, overtime becoming more proficient and trustworthy, to the point where they could keep their Miraculous.
>Have Chloe become an antihero post-S3. She could somehow get a Miraculous, probably given to her as a gift from her father, or get her powers from another source. Despite helping Paris and fighting Akumas and Sentimonsters, she ultimately wants to upstage Ladybug and be known as the one who defeated Hawk Moth. A possible redemption arc would be her learning to do good things overtime not for attention, but just being a good person.
>Make Hawk Moth a more competent villain. Does he want to bring back his wife or does he just want power? Why not have him try other stategies, like try to get Ladybug and Cat Noir’s identities or holding someone hostage?
>Do more with Lila/Felix, as they could make great secondary antagonists, as well as Kagami’s mom given her relation to Gabriel. Lila/Felix could act as scouts, directly dealing with LB and CN, while Kagami’s mom could use her resources to secretly assist Hawk Moth
>More side projects. The Miraculous Universe seems like it’s fully of so many potential stories, but I feel like Zag is underutilizing it. They could have another team create a comic that expands the show similar to Boom Studio’s Power Rangers comics. Make more chibi shorts to hold the fans over inbetween seasons and specials. Maybe even a licensed game with a new story could be possible. Given the series’ worldwide success, they could be great investments for Zag.