Where to start... Well, I like to begin with what a show did well, and unfortunately there's not much to say here. I thought the plot was interesting enough. Pretty typical for a human-experimentation centered sci-fi, but interesting nonetheless. When it comes to the story and any attempted plot twists, it wasn't that Cystal Blaze was boring, just very predictable.
Okay, let's just say it. This show's biggest flaws: the characters were awful. Manami has got to be one of the most selfish, annoying anime characters I've ever seen. And what's worse, just as she seemed to be starting to redeem herself, they drastically cut her screen time. As a duo, I found Manami and Ayaka to be irritating. It seemed to be their job, pretty exclusively, to get into trouble and then need to be rescued for the sake of furthering the plot. I hate characters who exist to be useless.
Akira was practically running his brother's detective agency, yet he never seems to do anything of consequence to the story. Shu's plotline with his on-again, off-again (because he's a cheating asshole) girlfriend was the only character storyline that I felt was done well... but again, I found it very predictable.
Any show with just plain unlikable characters is going to be hard to get into. But I feel like they all had at least a little potential, based on their setting. I really liked the concept of Rags Town being a place where people go to escape their pasts with no questions asked. But even if they weren't being questioned on their past deeds (which are all presumably dark), this set up a great opportunity for character development. What brought each member of the detective agency to this town? Well, if you were expecting an answer to this... even for just one of the many characters, you'll be sorely disappointed.
