I don't understand your thinking, mayby re read the beginning and think about Mc's personality a bit more
He's not trying to stop "Big things from happening", he's just trying to find ways where he can go through them again without having to experience the same pain he went through. He's not a saint (otherwise, he would've used his wish to save the majority, or he would've saved those peeps in the tutorial round), he's just an opportunist that doesn't want the short end of the stick.
And, this is just my opinion, but I think he doesn't want to change the events that much because it'll affect the future he knows and it may disrupt his plans and leave so many uncertainties.
That's what I'm saying though? Like he literally had the opportunity at the end of the game to go back to Earth with his friends that he had met in that world that he is in now so he really had no reason to go back 10 years and restart? It just doesn't make any sense to me because it's not like he's trying to change any of the big events that's happening that's why I'm saying that it seems like he only knows how to live in this world because he has lived there for so long already that he won't even know what to do with himself if he were to go back on Earth I don't really see how going back 10 years and going through all that hell again is an opportunity?
If I remember correctly, something went wrong with his wish so he couldn't revive his comrades that saved him when he was kidnapped. He could've gone back to earth, but that wouldn't have changed the fact that the "friends" He made in that world is already dead (not to mention it was his fault too). I haven't read the novel yet, but I heard he also went back time, out of spite, to get revenge on the angels that brought him there. Because -
Spoiler from another manhua
In it's sequel, he managed to banish a few angels to another world so they can also risk their lives to save it just like what they did to him and the rest of the earthlings with their world. Serves them right, I guess?
I thought his whole point of going back 10 years was to stop big things from happening? Yet it doesn't seem like he's stopping the grand(??) Lion from being the cause of the alliance war? And is instead just preparing for it..? and he could have saved his friends at the end and went back to Earth cause he had enough points for it so I don't understand his purpose?? I was thinking maybe it was because he wouldn't be able to live normally back on Earth after all the things he had done so he just rewinded his life back ten years which is the only reasonable explanation I can come up with as to why he rewinded time