While the premise is somewhat generic, this novel is one of my personal favorites. 

The pacing is good, transitions feel seamless, and the plot moves at a reasonable pace. The actions of all parties involved in any event are both understandable and impactful. The power system is well used and fights are always well crafted.  

Other takeaways, the side characters are fun and rememberable. Rarely, if at all, is there a character that is introduced for a single chapter then thrown away. The ending, while open, did not disappoint.