Well if I was to say that the mining, flying and shooting all felt like crap, yes that's my opinion but I'd not take someone who disagreed seriously (sorry) and what else is left gameplay wise? The vast majority of the time you spend playing the game, is not good, mechanically.
First off the shooter aspects are just terrible. Aiming is horrible and there's no feedback. It just sucks. It was obviously tacked on and nobody wanted it so it's easy to gloss over it but the fact is you're often forced into it so it cant be ignored.
The flying is a massive letdown. Not only is navigating around a planet much harder than it should be, but flying in atmosphere and in space are exactly the same. What happened to their amazing physics that other games don't have?
Even the mining, doesn't feel as good as say Minecraft. There's always been something satisfying about breaking blocks down in Minecraft - the animation, the sound effect, the satisfying pop. It's just another chore in NMS - confounded further by the abysmal inventory system. I honestly can't think of a game with a worse inventory system and considering how much you have to use and few features there are generally in NMS, that they botched it so bad is just pathetic.