Hmm, it's a little heavy-handed but I guess this character arc is alright, in the scheme of things. I feel like the author has been straying further and further away from Coco's main quest, though. I'ts nice to have a brimhat sighting at the end of this chapter to remind of us of the larger narrative.
Notice Agathe's personal development: from a cold-blooded killer-wannabe into someone who's simply grumpy and unkind even when all by her lonesome, with no one to keep pretenses before.