My Versions of the Trolley Problem

From wiki:
https://en.wikipedia.org/wiki/Trolley_problem
The trolley problem is a thought experiment in ethics. The general form of the problem is this: There is a runaway trolley barreling down the railway tracks. Ahead, on the tracks, there are five people tied up and unable to move. The trolley is headed straight for them. You are standing some distance off in the train yard, next to a lever. If you pull this lever, the trolley will switch to a different set of tracks. However, you notice that there is one person on the side track. You have two options:
Do nothing, and the trolley kills the five people on the main track.
Pull the lever, diverting the trolley onto the side track where it will kill one person.
Which is the most ethical choice?

My Versions
I tried searching for these alternate versions that I came up with and since I was unable to find any articles or forum posts with similar takes I figured I'd write about them. My thoughts on the subject mainly involve the Fat Man with or without the loop. If you've ever heard of these versions somewhere let me know.

The Fat Man and the Nuke
Again we have a trolley, a fat man, and yourself. Except this trolley has a nuclear weapon on it that will detonate if it reaches its destination. If the destination is reached a large city with a population of 10 million will be completely destroyed. For the sake of argument only this city with its 10 million residents will be effected. No physical or economic damage will happen anywhere else on earth. So the question here is if it is morally questionable to sacrifice the one fat man to save 5 people, at how many people would the decision to sacrifice him become easy? If you would not hesitate to kill the fat man to save 10 million then would you sacrifice him to save 6? 7? 100? 10,000? What if it was something involving the Death Star and you could save a planet of 10 billion people by sacrificing the fat man? If it is clear perhaps even blatantly obvious that you should save the planet then by the same logic you should save 2 people by sacrificing 1. I've seen similar versions to this with multiple trolleys and like 15 total people but never such a dramatic scenario.

The Fat Man and the busload of Babies
Would you sacrifice the fat man to save 5 babies? An entire class of pre schoolers? What if instead of death they would be tortured? Would you allow a baby or small child to be horrifically tortured or would you throw the man onto the tracks?

Baby Hitler and the Butterfly Effect
Assuming you had a time machine and could go back and stop hitler by killing him as a baby or somehow stopping world war 2 from happening in general by whatever reason, BUT if you did this you would change the events of history, while victims of the war would instead live, other people would cease to exist due to the change in the timeline. Is it murder to go back and prevent one from ever being born despite stopping a tragic war?