I admit I haven't really kept up with the media releases for this game, maybe I'm wrong, but this game in particular has way to much media hype surrounding it. I roll my eyes every time I hear developers talk about huge, varied, X number of things to do, advanced algorithms, only for the game turn out to be lifeless and soulless.
I would love for this to be the great space sandbox simulator, I did like Freelancer for its single player story and trading aspects so anything set in space is going to get my attention.
No Man's Sky is not a simulator, perhaps unfortunately for you (since that's what you'd love that game to be as you mentioned). You'd have to play Elite: Dangerous, or perhaps Star Citizen since they're both very much "space simulators". The devs for NMS is a small indie studio of about a dozen people total, and they certainly didn't have a hundred+ million dollars nor 4 or 5 years to work on it. I do believe that - very unfortunately so - too many people waiting for NMS are actually not aware of that and they think that it's a game that's out there specifically to "compete" against the big boys like Elite or Star Citizen. Too many I think will expect an actual proper simulation per se, only to realize that there's no very complex physics, nor atmosphere simulations, that the various upgrades for your ships are there mostly for aesthetics, and that the "dangers" you'll encounter on planets will mostly consist of rather simple environmental-based hazards.
If you go in knowing what to expect, then I think you'll have fun. NMS has an arcade approach to the "simulation" aspects of itself for very good reasons (low budget, small indie team, barely 3 years of work with that small team, etc; not to mention that going "arcade" with it might also have simply been a
choice from the start rather than an obligation due to their limitations as a team and the given budget). I don't expect each planets to
actually be "planet-sized" planets as they've been advertised so often, nor do I expect the various procedurally-generated life forms to have smooth, fluid and organic animations given the terrain they might have to deal with from time to time (imagine a spider-like alien on 6 or 8 legs seemingly walking on what looks like a perfectly flat plain when in fact the terrain right below it is full of small craters and crevices; there's limits to what procedural generation can do and how physics and animations respond to the terrain).
I could keep going about this but the gist is (to reiterate it) that it's a 6GB game with procedural generation of a universe, which has been worked on for about three years or so, with a small indie team of about a dozen people with a budget that has absolutely nothing to do with the one that fuels complex and big scale projects like Elite and Star Citizen. I hope that NMS buyers will take the game with a grain of salt and won't complain about how there's no "proper solar flares", or occasional earthquakes to which the wildlife reacts, or that the alien NPCs you'll sometimes encounter are always sitting down and never moving a single limb except turning their head to follow your movement when talking to them.
I've been expecting a game with moderate amounts of varied assets used by a procedural algorithm from a team of a dozen people since the past two years, and I still can't wait for it; but I'm not going in with the intention to ultimately compare it to anything else out there, much less actual 'simulation' games that seem to be in the same veins.