I got this idea a few days ago in the morning after having some really weird scifi dream...
Briefly:
"A man wakes up after many years in cryosleep only to find himself completely alone except for a computer AI. He learns that the humankind left the Earth many years ago. With the AI as his only companion he sets out on a journey to reunite with the people again."
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Well I tried to write here a much longer version of this idea though as I was writing it I felt more and more that it wasn't really good. But whatever, here it is:
It's year 21xx. The man wakes up. In the early 21st century he got into a cryosleep programme along with a few other people in hope that they will wake up one day in the future. The process was not reversible at that time so it could take years, tens of years or even hundreds of years before the mankind would know a way to revive them.
After he got into the cryonic state a lot of things happened. The technology got better and better, people created fully working high-performant hybrid computers - a mix of the semiconductor and quantum technology. They also created working nuclear fusion reactors which after some amount of time replaced all the other sources of electricity. As the time went by, people also created much better space telescopes.
Unfortunately, they discovered that a really big asteroid which would completely destroy the Earth was heading in the direction of the Earth and was about to hit it in a few tens of years. It was impossible for people to create a weapon or something to make it change course. Instead they tried to construct a faster-than-light propulsion system. Due to the technology advances and various physical and mathematical discoveries they managed to create an AI which was able to evolve and which would help them create the propulsion system.
After 20-30 years of thinking and computing the propulsion system was created. The nations of the world united and started to create big spaceships able to transport most of the humanity. By that time, many Earth-like planets were discovered. One after another, the spaceships were constructed and then flew off into space heading to the planet <some name here> lying several tens or hundreds of light years away.
Few years after departure of the last ship something happened that they didn't see coming. Another asteroid bumped into the first one effectively changing the course so that it would miss the Earth. Some smaller asteroids created by the collision headed to Earth thou.
The smaller asteroids kind of damaged the Earth and killed most of the wildlife and the people that still were on Earth.
After the departure the AI tried to find a way to wake up the people in the cryo......
Just the one man survived. I don't really know how it should be written in the story. Either the other cryo units ceased to work or the other people didn't survive the reviving process.
After that, the man tries to get to the people who left. Either he builds a small spaceship using robots and the AI and such or they discover how to create wormholes or something...
Or there could be a different ending. As he is looking for a way to travel the space he sees all the bad things that people are and were doing and decides to stay on Earth. To live with the animals and the AI (who's a female by the way with some cool abbreviation name like Shodan or Glados).
Or he decides to find the other survivors who are still on Earth and live with them.
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Ideally the game would have all three endings.
I tried to imagine the gameplay and there are three possible ways - a) a point&click adventure, b) a third person adventure (like a TPS but without the shooting as there will be no enemies) or c) an isometric adventure something.
I most probably won't ever do this game. If you'd like to do it I would be very happy and I would gladly help.
As it would be hard for me to do this as a game I could possibly make it a novel one day.
Just play Demon's Souls or Dark Souls

Really? In my experience, Atlus games are the epitome of grinding.
Oh well, this isn't the thread for that.
They aren't about grinding at all. They are completely new game mechanics. They are very hard but fair.