The character development and pacing are especially crisp in this. They cut out all the crap that makes a series drag on, such as awkward getting to learn new surroundings episodes that you can already guess what's gonna happen. It seriously never drags, and the story moves along at a brisk space. The team did a really good job of picking out the best scenes to make you invested in characters. I felt interested in most of the characters even though they've only been in the series for two episodes. Sure, there are plot elements that, looking back on it now, seem a bit deus ex machina-ish, but really didn't seem that way in the flow of things because they helped expedite development within and between the characters.
Music is mostly so-so. It's your typical anime OST stuff...it really doesn't belie how awesome its accompanying show is. But you really don't notice because everything else catches your attention enough.
They also end it in absolutely the most perfect way it could have. That's not something I can say for even some of my favorite shows in the past.
