BNA is great in some ways, and in other ways, it's not so great. What's to like? BNA is extremely artistic with a beautiful color palette. The animations are really good too. The voice acting is unique; it doesn't go for some of those really annoying voices in anime. In general, the best part is the art. Also, the final boss battle was really good.
The bad? The plot and characters. For me, the plot isn't that engaging; and I'm not saying it's bad, but I just wasn't that interested. BNA feels like it's going nowhere for the majority of the time. Michiru Kagemori (raccoon/tanuki girl) does a bunch of different things in different episodes without a larger plot. Granted, these episodes are supposed to develop the characters and the world, so I can't hate on it too much. When it comes to the characters, they're okay, none of them are all that interesting.
Overall, BNA is pretty average for an anime. The visuals are really good, and that's the best aspect of BNA in my opinion. The animations were smooth too. The characters aren't that interesting or likable, but at least the voice acting was good. Lastly, the plot felt like it was going nowhere until the last couple of episodes. BNA is a show that's not a must a watch; no one would miss anything by not watching BNA.