At this point, Pete and Maleficent in their current roles. I think Pete will be better served as a redeemed character. He would make for a far better anti-hero. I was hoping KHIII would end with Pete finally calling it quits because he seemed to be getting increasingly frustrated with Maleficent. Maybe that's the plan, but I'm not holding my breath given that Nomura doesn't seem to plot out things too well with these two.
Maleficent I don't even know anymore what they can do with her. Give her one more epic evil role perhaps and then just end her once and for all. Hell, have Pete deliver the final blow as the start of his new anti-hero role. I don't think anyone deserves to end Maleficent more than him given all the abuse he put up with and has become the voice of reason by KHIII.
Other than that, I just hope they stop throwing in so many random things that go unexplained for years. I mean we have only recently just learned what the device was in KH1 and how Maleficent came back in KH2...sorta.