That being said, if the time was taken, I'd love another musical episode.
The music in general takes a back seat in this series now that I think about it. The opening uses some weird chord progression that doesn't seem to get used very often... I like that though, The Final Countdown has the same progression so of course it makes a nice fanfare. I'm nitpicking really hard here, but... leitmotifs, if they exist, are kind of crossed up a lot... Outside of Cat Noir's specific transformation music, there's nothing to that effect going on, because the riff during Ladybug's is also present during Cataclysm. But again, I'm nitpicking and that sort of thing isn't absolutely necessary to exist.
When I was going through and searching for bgm though (most shows draw me because of the music and I was intrigued by the fact that I hadn't noticed it), I realized finding it is nearly impossible unless you're looking for the love theme from the umbrella scene, in which case everyone and their mom has done something with it.
Tldr: They don't have to, because the show is fine how it is, but I'd love to see the music team evolve to the point where they get noticed.