(I'm at work and making this up as I type so lets chat and come up with something cool together!)
FallOut 5 starts off with you waking up in a Vault (number doesn't matter too much here) but you have no memory of what happened, where you are, or who you are. You're groggy and looking around as you get up off of the ground, there's a high-tech mirror, it recognizes your face (customize here) and greets you with a Hello [Player Name]. Then a friendly face comes in.
"Oh my god! You're alive! I thought they killed... well, everyone."
You, not remembering a thing, are confused. Who killed everyone? Who is everyone?
"Man, they must've done a number on you, do you really not remember who I am?"
No. You don't.
The friendly face tells you where you are, who they are, that they're a family friend. They tell you about the vault and that, for the first time in 250 years, the vault's doors have been opened. There was a secret cult that had been forming in the vault for years, they killed everyone in the vault that resisted except for a few essential people; doctors, engineers, scientists. This included your spouse (doctor), and younger sibling (engineer). They took them into the wasteland to fulfil some prophecy that had been cultivated about salvation in the wasteland but knew they couldn't survive the journey on their own without the help of those who they took.
Your friend informs you that your parents are dead then tells you that they hid from the cult and watched as their own family was killed. They have been looking for survivors in the vault when they found you.
You want to remember who you are, and there's a guilt that sets in as you realize you feel a lack of emotions hearing that your significant other and younger sibling was taken and the rest of your family killed. But you feel obligated to find them, regardless of emotions. You know its the right thing.
Your friend can help you, point you in the right direction. They have nothing to lose and become your first companion.
There will be other companions along the way, and as you wander the wasteland in hopes of finding the last remnants of family, you have flashbacks to inside of the vault, giving you pieces of information to who you are. These flashbacks happen when you level up, the story allows you to make choices that will increase your skills and pick new traits. (Brief example, flashback to you as a teenager, the friend that finds you is also there and there's a situation that requires quick thinking. You make choices there and at the end of this flashback it tells you what skills should be increased based on those choices, but ultimately you get to adjust those points to the areas you want.)
I originally wrote that they took your mom and two siblings, and also thought about it being an outside group who killed everyone in the vault for resources. I'm thinking this vault was given high tech equipment, like the futuristic mirror, and that's why it was raided? And so the only people who knew how to operate, engineer, and create more of this kind of technology were the people inside of the vault and that's why people were taken. I'm not sure, I feel like there can be holes with that one. I ultimately think that either way the Player was supposed to be taken with the group for their knowledge of whatever the end goal is, but their inherently good nature tried to stop the attack and they were shot or something but we don't discover this flashback until some of the last levels/quests.
Not sure how this would end yet but let me know what you guys think!
Oh and post apocalyptical Chicago? I was thinking there because the graphics would be so cool with the high rises, the great lakes, lots of city space to play around with. Or someplace like Florida? But like imagine the swamps in the apocalypse. And all of the crazy animals down there that could be mutated! The people down there are scary today, imagine the crazy ghouls and other creatures radiation could do with Floridians, haha
Another FallOut Game Idea
Like before, I'm just typing as I go...
The game starts before the war, like in FO4 however we get to play as a family for a while and it determines what vault you get assigned to. I assumed that people got put into vaults based on location, however some people in that location were rejected. So what if in this gameplay, you get to do the "application" and its similar to the G.O.A.T. and you get to see which vault you would be sorted into.
The experiments the vaults had to have similar control groups. Ones that would best give a reliable outcome if the base is genetically or mentally similar. So in a new game, there would be the application before life. You play that life for a bit with a family. Spouse and kids. You get put into one of the few vault options this game has.
Flashforward, you're looking at an old photograph of the family. Then someone comes in, one of the children in the photograph is now your grandmother and is talking about life before the war and how she wishes she could see the outside world again. She tells you that you look just like her mom/dad (whoever you designed in the beginning.)
You're a child and you get to do things similar to FO3 in which you do minor gameplay within the vault-- determine your S.P.E.C.I.A.L.s and skills and whatnot. You get to explore the vault as a child. The children are kept separately from the adults. The choices made before the war determine what kind of career your family went into. We now transition from solo player to multiplayer mode. You meet players that were also assigned to that vault and choose to befriend them or not, but you must all pass the level before moving on to the next stage. (Might be an issue but comment how that could be fixed). You never interact with the other players family, so the story can be virtually the same, just minor tweaks for personal characters. Like if someone's family was in sciences, your science is automatically a point higher. Same with the other specials and respected professions. You do minor challenges and tests and stuff to determine who you are, what your vault's experiment was, and, when you befriend someone, you get to see their skills and S.P.E.C.I.A.L.s too!
Then, after a few "levels," you're 20 years old and today's the day the vault doors open. You can choose to travel with people from your vault, go solo, or team with other people from other vaults to explore the wasteland and do challenges and quests.
I think the biggest issue I personally had with FO76 was the lack of story. I love how story driven the previous games were, but I'd love for there a main story that you/ your team must do together to complete the game. The goal is to finish. Maybe another vault's goal is to sabotage the other survivors plans in secret? Endless possibilities, lets chat!