#plus it ties Marinette directly to the main villainous plot of the show

[mlbirb]

There was so much potential for Marinette to be the Peter Parker to Gabriel Agreste’s Norman Osborn. Both are ‘genius pairs’ in the same line of work (science for Peter & Norman, fashion for Marinette & Gabriel), both are a supehero/supervillain pair in disguise, and both Norman and Gabriel have a son that they treat like crap who’s friend with the protagonist.

It would have made the villain/hero conflict much more emotional.

Gabriel, Audrey, and Su-Han. The trinity of adults who eventually learn to respect Marinette's talent, then begin treating her like cr*p. (Additionally, that society of guardians doing jack about supporting their newest member.)

Gabriel could’ve had a connection with Marinette through fashion that would’ve made the eventual reveal/his defeat hold more weight but noooo. He’s supposedly her idol but there’s no relationship to connect them.

Her being his protégé could’ve also made his desire to akumatize her in “Ladybug” or “Chat Blanc” make more sense, cause as it stands we have no clear reason on why he thinks she would be a particularly powerful akuma.

Audrey could’ve been in the same boat, having Marinette as a fashion protégé. She could’ve shared a connection through designing and had the drama of Audrey continually favoring Marinette over either of her daughters but not in this show apparently.

Or since Gabe’s eventually gonna (hopefully) be in a prison cell or 6-feet-under by the end of the show, Audrey could still have been Marinette’s big connection to the fashion world into adulthood, but she (maybe?) threw that away to reconnect Chloé with her mother.

Su-Han is maybe the biggest disappointment of these 3. Marinette could’ve had a good mentor figure in him after Fu’s departure. Someone who knows more about the Miraculous and the Order of the Guardians than Fu did. Especially since, as you said, the rest of the Guardians from the temple don’t wanna step in to support her.

But he’s barely been used since his debut episode, and he spent most of his time in “Ephemeral” chewing out Marinette due to Chat not being present during a fight.

So much potential wasted.