I decided to do this review in two parts because it would be more accurate to judge the series pre- and post- Soul Society.
The characters are well-developed, with each getting a short arc in the first part of the series, and each bringing out different sides of Ichigo’s personality. Even minor characters have interesting personalities and backstories. Ichigo’s development is especially interesting, as he comes to understand what it means to be a Soul Reaper over time, and his own reason for fighting.
The Soul Reapers are interesting antagonists with a variety of personalities and motivations. While many try to prevent Ichigo from stopping Rukia’s execution, others oppose it, others don’t care and still others are more concerned with other issues that eventually prove to be relevant to the execution. Byakuya is an excellent example, as while he appears wholly devoted to the law, he is inwardly conflicted. Kenpachi serves well as a terrifyingly powerful enemy and later as a surprisingly useful ally of convenience. The revelation of who is responsible for Rukia being sentenced to death is quite surprising and effectively helps resolve unaswerd questions.
The fights are often intense, but unfortunately, Ichigo has few abilities beyond sword slashes and occasional energy blasts, limiting the strategies he can perform. Despite this, the battles are well choreographed and include a variety of foes, keeping things interesting.
There are some flaws to the story. Ichigo’s friends do relatively little that impacts the mission in the Seireitei, as they mostly end up separated from him and struggling to meet with him. The anime removes a fair amount of material from the manga, especially scenes hinting that Orihime is developing feelings for Ichigo, and some of the new scenes, particularly those in Episodes 8 and 9, cause plot holes. However, it tends to be somewhat quicker-paced than the manga, and often covers as many as three chapters per episode.
The manga has a surprisingly good amount of bonus content, like sketches between chapters providing background information, or showing what other characters are doing, as well as flashback chapters that reveal more about characters.
This series is quite good. The manga is better than the anime, but the anime is still good at putting the fight scenes into motion.