Well, it's not first-person, for one thing.
As for the rest, I have to guess--since I'm not part of Stardock--but based on how similar this seems to SC2 (which came out way before NMS), I think these won't be way far off:
It has a well-defined story, unlike NMS.
Interactions with aliens won't be so stupidly generic; they'll actually speak to you like you're having a real conversation.
Those interactions will lead to story-changes.
I'm sure the Stardock crew can tell you more, but those are the ones that stick out to me first.