Wouldn't it be nice if there's a post-apocalyptic open-world game with seamless transitions between areas, but shares the same signature gameplay and thematic from That Game Company's Sky: Children of the Light game? 

It's like, bringing back peace, harmony, friendship, love, and humanity to restore a world that was driven into an irreversible catastrophe by humans. 

Make it so that it also uses the idea where the game would also have a great replay-ability so that players won't have a post-climactic feeling after finishing the story quest to lose purpose and quit the game. 

A new idea that I would be suggesting, is to have elements of procedurally generated loot system where you have to make a fair amount of effort to find good loot, whether it's useful tools or cosmetics in the game. 

Surely, monetization is always present in games, but please make it so that it is fairly priced and are following the new guidelines in EU where the equivalency of real to in-game money is balanced.

Hi, that’s a really good idea, a positive post-apocalyptic game where you restore humanity, civilization, or even something small. However, I would argue that many games similar to TGC’s vision, and even some of their own games, are already somewhat about that. Sky: Children of the Light, Journey, Rime, The Last Guardian, in these games, you explore a world where something has already happened. You play as a passerby trying to figure out what occurred, trying to escape, or simply enjoying the scenery. That said, I agree that not many games have gameplay directly focused on restoring the world. Sky does it to some extent, but there’s definitely still room to explore that idea further.

scope is always a factor when hypothetically designing a game. Maybe start small and expand on that idea first. Post apocalyptic room or rooms which interact with one another (duplicates which change over time) one room, multiple changes in timeline. Small and sweet, once you finished that. Than expand to the outside world.