The plot of the Arc is basic and not much events occur. Character-development of almost all of the characters (except Rengoku and Tanjiro) is almost nil. The sudden appearance of the character of Akaza is also something which is odd.
However despite all this shortcomings the Arc stands tall. The splendid animation, the background score, the awesomely directed action sequences, the powerful ‘blazing’ character of Rengoku and the emotional touch to Tanjiro's character is what makes anyone watching it entirely ignore the shortcomings. The Arc also properly highlights the emotions of people who would love to dwell on dreams of the past and their struggle to come back and face the reality.