If we're talking about things we'd like to see in this DLC, I have a few thoughts too.
More than anything else I just want more character interactions. Those scenes were where KH3 really shined, but for many of the cast it wasn't enough. Namine had exactly zero dialogue with anyone but Sora. Her playing with Xion at the end was nice, but not nearly enough. Have her and Kairi and Xion talk together. Xion, Axel and Roxas also didn't get any deep interactions after they were reunited. Roxas and Ven had that funny moment where they see each other, but it was only a second, need more of that! And more of TAV interacting with everyone else too! Playing ultimate frisbee was fine and dandy but I want so much
morrrrre.
My go to comparison for that sort of thing is the Mass Effect 3 Citadel DLC, which was just, ugh, so brilliant. So perfect. Mixing combat missions with a big old party where everyone who ever served under you on the Normandy gets to hang out and interact
and get totally plastered
I mean frisky
I mean possibly steal things from your apartment Kasumi I'm watching you
Next thing. From the trailer, we know about the other playable characters in the final boss gauntlet. Well I think there should totally be a Kairi vs. Master Xehanort fight. Even if it's one of those doomed boss battles where you win but then you get knocked out after, at least it would let her get to take some damn
action, not treat her like a helpless prop.
Last thing I can think of is another round in the final battle. We got to fight epic, giant versions of Ansem and Xemnas in KH1 and 2, but where the heck was our giant MX? A giant-fused-with-KH-old-man fight? I loved those boss battles in the other games and was disappointed there was nothing like it here.
I also wouldn't mind getting new bgm for it. It was kind of a big letdown during every round of the final battle to just hear Rage Awakened over and over and over again. Plus it made no musical sense. Would've loved some awesome blend of Destati, Xehanort's theme/Key of Darkness, Dearly Beloved, some mix like that.
Anyway, that's stuff I'd include if I was in charge of the DLC. And I expect exactly zero of those to happen