Alright, I have a giant Mindfuck after playing the game, It's An artistic and mental masterpiece, not only it allows self-reflection on our current world situation but the art style also shows how well a game can come out IF you put enough effort into it. But I wish to expand my point
1st of all, the game's art, Is just a visual masterpiece, it shows that the Artists put a lot of effort into it, even at a glance, the anatomy is drawn, well and pleasant for eyesight, and there aren't any bugs, or forms of visual error that I could spot, however, I am not an artist and my simple brain enjoyed that style of art, however it can and probably will be to everyone's preference, but to me it was just great, nothing bad I can say about this part, and nothing else that I want to say, summing up the art style was just great.
2nd, the philosophical aspect of this game and other mental implications, storyline... now, before I start I want to say, that I am still in shock, so if anyone is reading this please don't take this personally. EVERY single ending contains the fact, that WE as a species committed the same mistakes every single time, however even though it's counter-intuitive, we are learning from the same mistakes, the reason why humanity progresses as far as it is now, the reason why we can comprehend just a grasp of the infinity of horrors is because of OUR intellect, of our choice with what WE decide to explore, the mistakes that we keep repeating, war, suffering, progresses us further, and builds as species, it's natural that we will progress, and with that progress issues and mistakes will come, however, WE will overcome it, why? Because that's what humans are, adaptative intelligent species, that's what WE are and the main protagonist IS, even though he doesn't express the usual desire for the voyage and with its horrors and other terrifying facts of nature, he still has it in his genes, Because he is human, I wouldn't say I like the fact that the Human character had a pretty crucial part stripped of him. However he is still a human and has hope for humanity, and himself, "We concluded that humanity is selfish" That statement is incorrect, it's a species that grows GROWS and Expands, and it will need all its resources for the population, that's the natural cycle that we try escaping, Humanity, bringing such obvious facts is an interesting to attempt at emphasizing the human nature, however, that's what makes human a human, selfishness, and learning even more from the mistakes that he committed, I don't like the fact that the game is treating human value, and us as a disease, as our mistakes, and "selfishness" is part of us. The telling of that was done poorly, making humans look like the bad guys, while the main character is a "Bad guy" Yes he DOES try "redeeming" himself, however, that is just stripping human, out of his humanity, humanity is not only our intelligence, it's our adaptation and fast ability to learn, and expand not only as an entity but as species, humanity has remained That from its start of recorded history, the game undermines us, showing only the negatives, without waging the benefits that come from it, it presents humans as inferior creatures to the species presented, that is not the greatest part of the game
3. The storyline, alright sorry for my rant, in my opinion, it was necessary, but once again sorry, The storyline is good, except for the part where "humanity failed" and the terra situation... however I will talk about that later, the game got a great plot and storyline that's fitting for a game with h-scenes, the game showcases the great variation between species that may represent humanity's values, however, it's up to one's interpretation, furthermore, the endings were on top, they were just great, not only wholesome but there is a rather good amount of variety between them, I enjoyed each of them, however, the story behind terra (Earth) does not fit with me, humanity can't mess up earth that badly, even though they could mess up it that badly, we'd have the ability to spread onto other planets... with that kind of technology, even though hundreds of years have passes since the ships started their course I'd like to imagine the fact that we didn't go extinct and somewhat succeded, and our story wasn't over covered by the cold and dark universe, anyways, besides the terra part which was needed for plot convenience, which I can and will forgive, the story is great, and wholesome, it really is a fitting story, regardless of prefrences.
Summing it up all, the game is great, it's worth all your time, and you should try not to pay much mind from the philosophical standpoint, as it may just lead you into a rabbit hole, which you will go deeper and deeper... the story has a good depth that's fitting for a game like that. I recommend playing it, it will be worth all your time.
(Edit: Forgot to mention that, the game has alot of plot potential for the future, it's a shame that a sequel isn't planned)