There's a massive modding community for the game creating mods that provide quality of life changes, texture packs and even new races beyond the default humans. Planets are randomly generated based on seed and each planet has hundreds of unique map tiles for you to settle in.

All the while you're beset upon by opposing factions, mad animals and the world itself. Your pawns arrive there by different scenarios but the main goal is always the same: survive long enough to research how to build your own spaceship and ride it back into space. I don't know if many people here play RimWorld but in case you don't, it's a colony manager/simulator where you assist your pawns to create a brilliant base on an unknown rim-world.