I also think the engine of No Man's Sky could be a basis for many other types of games that have a fuller story in them, such as Homeworld, Freespace, Mass Effect, Star Wars: Knights of the Old Republic, or Master of Orion. In comparison, there is some story in the Atlas quest of No Man's Sky, but the story is slim. There is almost no conflict with other living things in the game, other than with random bounties, space pirates, sentinels, and the occasional animal. Once, an animal resembling a Tyrannosaurus Rex attacked me next to my ship, and I shot the creature with a grenade launcher. The greatest enemy on planets, though, is the environment on hostile planets, which can be hot, cold, toxic, or radioactive. The game is mostly about gathering resources, managing them in limited space on your ship or in your suit, creating things with the resources, and exploring on the ground or in space. There are random situations in which freighters will send out a distress signal, because they are being attacked by pirates. You can choose to help or to let them die. Early in the game, you will probably die if you try to fight space pirates until you get some ship upgrades. There are occasional random space ship bounty missions where you get 10,000 units of currency for destroying a fugitive ship. Occasionally, pirates scan your cargo and jump into the solar system to attempt to kill you. You can occasionally find a crashed ship that you can repair and fly. That becomes much easier once you learn to manufacture things from knowledge gained at manufacturing facilities. A quest system would make the game better, like in The Elder Scrolls: Skyrim game.
Flight over terrain in No Man's Sky is highly automated, so you cannot crash into the ground even if you want to do so. The game would be more interesting and fun if your ship takes damage from pirates or sentinel ships in space combat and you have to control your crash landing to the extent you can onto a nearby moon or planet. A player's heart would start beating faster if a message that the flight control computer has failed is played along with the alarm sound of a failed deflector shield as the pulse engine propels your ship into a planet or moon as the last ditch effort of the flight computer to save you as the heat of atmospheric re-entry starts to be visible on the windshield. If you crash into water that is too far from land, then you could become exhausted and drown unless you use the existing gear in the game that lets you breathe under water. Another option would be to occasionally have to land the ship like in the arcade game Lunar Lander, but in 3 dimensions in windy conditions.
Currently, there is no reason to ever go swimming that I have seen in the game. Swimming seems to be a complete waste of time and not worth the risk of drowning. Being able to recover a ship that crashed in water would making swimming worthwhile. A ship that crashes in water might have fewer damaged systems that need repair. There are occasionally buildings and monoliths underwater, but the buildings tend to be embedded in the indestructible sea floor and are impossible to enter.
One time, I found a crashed ship with more cargo capacity and transferred all of the cargo on my existing ship to the crashed ship and began to fix the damaged systems. The game crashed. When I restarted the game, the crashed ship with all of my cargo was gone and I was left with my empty original ship which I had dismantled as much as I could to repair the crashed ship. I alternately took ownership of my original ship and the crashed ship to transfer inventory items between the ships to make space for repair items that I needed to create.
The gravity is the same on every planet and moon, like in Mass Effect. Some variety in gravity might be nice to have.
There is some boring repetition in the game. For example, some of the buildings require you to solve a number sequence puzzle, which gets repetitive once you have solved them all. The multi-tool examination device that gives upgrades to your multi-tool will eventually keep telling you that you already have a particular upgrade. Once a player has all of the upgrades for their multi-tool, then they should no longer have the option to even try to upgrade their multi-tool. There is one health +3 upgrade that I obtained but which I cannot build in my exo-suit. I think it's a game bug. There is also one environmental shield called Tau when you obtain it but displays as Theta in your exo-suit. The sequence of upgrades is: (1) Sigma, (2) Tau, (3) Theta, and, sometimes, (4) Omega. There are passes called Atlas Pass v1, v2, and v3 that can require many attempts to get. You get them by raiding Operation Centers or Manufacturing facilities which have a reinforced steel door that you need to blow open either with a laser or with a grenade launcher. The grenade launcher works faster than the laser and does not alert the floating sentinel robots which seem to be everywhere in the game except in caves and under water. Sentinels are apparently deaf. If they are looking away when you blow open the door with a grenade, then it is as if it did not happen, but if they see you using a laser on the door, then they attack you. Once you get inside, you have to operate the controls of a computer that displays a message in an alien language to select the correct option. You might understand some of the words from knowledge stones, monoliths, or from having conversations with aliens. Getting these Atlas passes allows you to enter places in some rooms in space stations or in some buildings on the ground that are otherwise locked. The rooms may contain plants, cargo containers, an exo-suit upgrade device, or a lounge with a table and chair. The plants are useful for getting carbon, which is the first ingredient for making hyperspace fuel cells. Blowing open the reinforced steel doors was always fun for a while until the computers inside kept saying that I already had the blueprint for an item.
Gathering resources that you can resell to get a better ship can be a grind. A ship with 48 inventory slots can sell for over 100 million units. In the entire journey to the galactic core, I earned less than 12 million units of currency. I eventually got a 48 inventory slot ship by repeatedly finding and repairing crashed space ships which always have at most 1 more inventory slot than your existing ship. Some asteroids can be mined by your ship by shooting the asteroids with lasers or photon cannons. The type of star in the system seems to affect the minerals that you can find in the asteroids. In all solar systems, most smaller asteroids are made of Thamium. Larger, potato shaped, asteroids can be made of copper, iron, nickel, iridium, gold, aluminum, or a substance in the game that is called Emeril. The explosion effects on large asteroids are really nice looking. I'm surprised that blowing up larger asteroids to protect a space station or large ship or convoy was not one of the missions, like a 3D version of the arcade game Asteroids.
Despite the huge odds against coming across the tracks of other humans in a galaxy with 18 billion billion systems in it, I have come across the discovered systems of 4 other people. I found one planet near the galactic core named by a Twitch player. I discovered for myself one planet that resembles Earth with one moon which I named, "Eden," in the, "Eden System." Perhaps one day another player will find it.
No Man's Sky is a game about dealing with limited information, limited resources, solving a fixed number of math sequence puzzles, and exploring a big galaxy. You can choose to go to the center of galaxy and find what is there, or you can choose not to do so. No Man's Sky is a generally relaxing exploration game that is open-ended, like life.