Asklemmy

The Last Jedi doesn't happen the way it did. Instead, the moment on the island where Rey tries to hand Luke the lightsaber has him reject it in anger and anguish, afraid that the past he thought he had left far behind him has re-emerged. It does not get casually tossed off the cliff for a cheap giggle. The reasons for the rejection can be broadly the same, if necessary, but they can be shown in a less weird and melodramatic way.

In this new version, Finn gets something (anything) to do, ideally something that will bring he and Rey closer together by the end.

Poe does not play "Can you hear me now?" with Hux. There is no casino planet, no obvious double cross and no little moppets with magical broomsticks.

Luke does not die at the end. Leia dies at the 2/3s point, and it's this that finally brings Luke back into the fold, perhaps to get revenge, perhaps to honour her dying wish, whatever.

Snoke is not discarded like a used tissue. Kylo and Rey still communicate psychically, but there's no hint of romance. Instead he starts to tempt her towards the dark side, leveraging the pain she feels towards the parents who abandoned her.

I dunno, just something which follows on more naturally from TFA, which is darker, and which definitely is less silly than what we got.

The Rise of Skywalker is in many ways the same as in reality, but it's Snoke and not the Emperor that's the Big Bad (although maybe you get the Emperor involved as some sort of Force ghost mentor to Snoke, or whatever). It follows on much more naturally from TLJ, because it doesn't have to spend the first 30 minutes doing major course corrections. Finn and Rey get together, only for one of them to be killed off... or were they?

I would tackle some of the sloppiness of Fallout's lore in relation to the Bethesda games.

Primarily, I'd set Fallout 3 like 25 years after the bombs instead of 200. It never made sense to me that creatures or people can survive 200 years in a location with poison water. I'd have to take out the Ghouls or alter the lore there a bit, though.

I'd revamp the plot of Fallout 4, either making it totally about the synths or removing them entirely, and also set it shortly(ish) after the bombs fell. Bethesda doesn't necessarily make bad games, they just don't fully consider established canon before making creative decisions. Which irks me tremendously, because really all you have to do is hire one obsessed nerd and run decisions by him.

Warhammer 40k, dumping at least half of pyrrhic shit and needless grimdark but also bringing back the old lore that humans caused chaos.

I give Monolith Soft the funding and popularity needed to be able to create all 6 originally planned Xenosaga games instead of the 3 we got

Command and Conquer - the Tiberium Saga. Leave Tiberian Sun and Firestorm alone, modify C&C 3 to have better continuity with Tib Sun and Firestorm on the state of Earth (i.e. Tiberium Fauna and Flora, further degradation of Earth environment). Remake C&C 4 where base building is part of the core gameplay element again, and delay the deus ex machina effect of the Tacitus such that the Earth is not in such a pristine state as what we do see in C&C 4

Spider-man one more day. Just let aunt May die. Have Peter go to therapy or something for the grief, then years later do a reveal that it was Norman Osborne the entire time.

I’m shocked nobody has said game of thrones yet

This one's easy, Warhammer 40k, and all the nonsense about primaris and guilliman returning.

Jeremiah, Jericho, dead like me.

They were all great ideas (though jericho wasn't necessarily original), that if you grabbed some great writers could be modernized to be awesome. But since they didn't have a wide audience, they never will happen unless I use this power. Most of the others mentioned here will eventually get redone.

at least half of Dragon Ball Super