* No explanation how Roxas can still DW (Nomura interview probably, typical)
* No explanation as to how everyone suddenly remembers Xion (Nomura interview probably, typical)
* The screen time for the characters were abysmal, that I can't even be upset at Naminé being saved until the end cut scene. At least she didn't have a weapon. It was basically group A, they get reunited, happy tears and hug, now let's head to group B, same thing, now let's head to character C, who has closure with Riku, sad, sacrificial moment. Have them all gather to stand around together in the background, have one or two throwaway lines, Roxas and Ventus doing the Spiderman meme without the finger pointing, and that was it. Not too in depth. Rushed.
* You literally have a character with powers over everyone connected to Sora, and you couldn't do anything else better except shafting her until the very finish? You have, legit, a plot device, that can solve some characters' return in the most simplest manner without having to convolute anything, which Nomura more than likely will. Man, he's lucky he screwed everyone else over with screen time relevance cause oh boy, I would have gone to Japan to personally choke him. You have such a limited amount of females as is, and you leave one out? Nerf another, and...
* I can't even mention Kairi's name. Poor gal. I don't care for her and Xion whatsoever, but it's gotten to the point where her treatment as some manpain tool (something Xion also served as) is making me feel so bad for her. And she's not even a bad character, she just gets sidelined, told to take care of Mickey, Donald, and Goofy, gets kidnapped, and offed. She managed to help Sora find the light, yet they did not keep up with the momentum. The biggest disappointment. She was rather hyped with being a fighter and failed to deliver.
* Naminé has created many connections in this series. We only get to see a few seconds of her interacting with Riku and Xion, but not Roxas (shipping aside, they did make a promise and all that jazz that amounted to nothing), or Sora, or Kairi, or Terra, or going into more detail with the scene when she wakes up and sees Ansem the Wise. Didn't get to witness her reaction once she found out what Riku Replica did for her. We don't get to see the reunion of Roxas with Hayner, Pence, and Olette when he returns to them, no scene of Isa apologizing to Roxas and Xion, no scene of Ansem apologizing to Roxas (goes back to Naminé), Roxas and Sora don't even actually talk to each other, Riku and Xion don't get to have a conversation. Roxas and Ventus was already mentioned, we don't get deep information on how all these characters return other than the BBS trio, we just get it summarized by exposition. Rushed.
* Sora never got to thank Naminé, making the implications of this in CoM, Coded, and DDD pointless (the Dive to the Heart also has you choose a Sora and Naminé scene). It falls into the same bracket as Roxas and Naminé.
* No explanation as to why Xemnas never used a Keyblade despite being able to due to being connected by way of two wielders...doubt Nomura will ever open that plot hole.
* Not touching Master Xehanort.