Crown of Midnight is a long fast paced mess that needs some cuts here and there. Besides that I´m here for messy books. The plot and storylines get chaotic but very creative. While the first half reminds one of Throne of Glass, the second half develops a completely new plot. 
Finally, some characters get a good development while others feel inconsistent.

I start to enjoy Celaena more than in the second book and am curious about her being a Fae. Dorian stops being annoying and acts fairly civil while Chaol has hit or miss moments. Archer didn´t feel very fleshed out and acted very inconsistent. Lastly, Nehemia´s death was potential thrown out the window.

This book definitely shines with its emotional roller coaster but has weak points when it comes to the plot. 
Overall I had a fun but chaotic time reading and feel a bit intimidated but ready for Heir of Fire.