"Covention" seemed to be setting up Lilith as a mentor figure to Amity, paralleling Eda and Luz, but when Amity needs someone to help teach her in "Adventures in the Elements", her older siblings Edric and Emira fill the role instead. Not only does the idea of Lilith as Amity's mentor never come up again, but the characters would never directly interact after that episode, save for a brief hug in the Time Skip montage of "Watching and Dreaming".
"Understanding Willow" has two:
It's revealed that Amity broke off her friendship with Willow as a result of her parents, and the episode ends with Willow stating that while they aren't friends again, Amity's actions in the episode were a good start in mending things between them. You'd think their interactions going forward would carry some hints of hostility or awkwardness as they try to fix their relationship, but this doesn't become a plot point until late in season two; long after Amity has already integrated herself into Luz's friend group, with Willow and Amity having several easygoing interactions in the interim.
It's also revealed that Amity's friendship with Boscha and Skara was arranged by her parents in order to better fit the high society. This could've been a perfect setup to contrast her fabricated friendship with Boscha and Skara to the genuine friendship that Luz has with Gus and Willow, the latter being her former friend. However, no real comparison is made and Amity breaks things off with Boscha and Skara in "Wing It Like Witches", just two episodes later.
Amity's broken leg puts her out of commission in Season 1's final two episodes, despite her still being able to walk. While her internal conflict and drama over Luz and later Lilith turning against the Emperor would have needlessly extended the runtime, many were disappointed that her role in the episode was nothing more than a reaction shot, wishing that could have at least conversed with Willow or Gus at some point, or learn Luz was planning a dangerous heist and was used as a human shield.
Lilith creating a scrying potion so that the Owl House gang can spy on castle residents was completely forgotten about after "Separate Tides", not even being mentioned when Lilith returned in "Elsewhere and Elsewhen", despite how useful it would have been as the characters became more aware of what the Big Bad was planning.
"Yesterday's Lie" properly introduces Luz's Doppelgänger Vee (aka "Creepy Luz"). When it's shown that as opposed to Luz's Friendless Background before the start of the story, Vee managed to connect with others and develop a friend group, it was thought the show could have had Luz use that to reflect on her own life in some way, questioning if she still could have been happy if she didn't end up on the Boiling Isles. The fact that Vee is living such a different life from her is barely addressed.
