Story: I'm disappointed because I really liked the premise of this series. I thought it had promise but fell short. It felt a little all over the place. The individual stories were nice but they didn't seem to mesh and give a overall plot. There were also too many ideas that were introduced and not paned out well. If there's a sequel that makes up for the what the series was lacking then that will be good but otherwise, it falls short. However, it definitely does have unique ideas and does cause you to think.
Animation: Really nice but can be a little scattered. I will remember Dantalian but not the others design-wise. The backgrounds and details were exquisite though.
Sound: I don't remember much. The seiyuus were ok. I liked the opening and ending though.
Characters: Same as the plot. The character relationships feel like they could have had more depth.
Overall: Interesting premise that falls short. It's not a complete waste of time but without an adequate ending, you'll end up being disappointed.