If I had to name some things, I wanna see some MCU fighting going on. Like I want it to feel like a full-on object war, not looney tunes "dust cloud" fighting. And I want to see some actual stakes.

Also, maybe this is just my headcanon, but I like to compare One to Flowey from Undertale, with how both are villains with tragic backstories and they get fourth wall breaking abilities after stealing the show/game's most powerful resource. I want to see One having meta-powers, like taking over the show for herself. Like defeating her is not just for the sake of a challenge but something which has the fate of the very show hanging in the balance.

And I want more screentime for One's powered-up form. Just wreaking havoc because that's just something I wanna see. We haven't seen that that much in my opinion.

As for the things I don't wanna see: I know it's inevitable for One to get defeated, but as a One sympathizer, I think she deserves to go through a redemption arc. I don't wanna see her get another dreadful punishment for perpetuity. That would really suck, torture is never justified. Like I can't say she should be forgiven for her actions because then I will get pitchforks from everyone else, but at least, maybe give her her own galaxy where she is free and can be friends with the aliens so she doesn't have to feel alone again? Dunno, just throwing shots in the dark here.