Quoting myself here because I'm amazed at the difference between how much I enjoyed the first few hours and how much I hated the last few hours before I returned the game. I logged 12 hours on the game. In the end, I just kind of got bored with it. The solar system wasn't even moving around. The sun was in a skybox and the planets hung around in the air in fixed positions.
Then I started watching videos of the features that were promised but not delivered, saw the ending of when you reach the centre, watch the videos of Murray blatantly lying about the game in his interviews, and just decided the game's not worth the 60 bucks I paid for. Got a refund from GOG.
It's the first time I've returned a game. I like to think I have the self control and bullshit detector to avoid buying lemon games, but damn, this game got me good.