Im not sure how this slipped under my radar at the time of it's release. Houseki no Kuni is by far one of the most interesting and unique anime i've ever seen.
The whole story and setting felt so fresh and it was the first time i have been so intrigued in an anime in ages. I was constantly trying to predict what would happen next in the show, because it seems really predictable to be honest. However, i was wrong nearly every time and the anime just continued to amaze and surprise me with it's twists throughout the story. My one downside to this though is that it isn't complete, and doesn't have a conclusive enough ending for me to feel satisfied. Your still left with so many questions after the anime finishes. Honestly left me with a bad taste in my mouth, and i will be reading the source material because of this.
The soundtrack fit so well with the series. Depending on if it was peaceful, if there was bad guys around, if a mystery was brewing or whatever, the soundtrack changed to fit the mood. I'm aware that all soundtracks are like this, but this one just stood out to me.
Another thing that stands out about this anime, and is probably the first thing people notice, is the art style/animation. All i can say is that is is so beautiful and amazing. The visuals in this are just stunning
Overall I highly recommend everyone to go and watch this. I'm not sure how so many people, me included, missed this.