6.5/10
First things first, the animation is beautiful albeit a bit shaky at times. The original score is beautiful but the rest of the music was quite disappointing.
This show definitely feels like a missed opportunity. The world building (both figurative and literal) is interesting and makes you want to know more about the back story. However, the main issue of this show is in its writing. The plot twists were either easily predictable or straight out of left field. The characters all seem very one dimensional apart for the one or two outliers whose character arcs evolve either too suddenly.
Unfortunately, the exposition in the first few episodes made it seem like the writers felt the need to hold your hand for you to understand their concept. On top of that, most of the dialogue between the characters is simply not convincing enough to believe they are real (which is pretty ironic considering how the characters come to be).
By the last episode, i didn't feel particularly attached to any of the characters.
There were a few plot holes yes, but nothing that had a major impact on the show in my opinion. Watch it if you have some time to kill but don't expect to get your mind blown.
One last thing i forgot to mention: the action sequences were laughably rigid and poorly choreographed but hey, that wasn't the point of this series.