Complex sentence: Many critics and commentators consider "Charulata" to be Ray's greatest achievement, with Ray famously remarking that it had the "least flaws" of all his movies, and "Charulata" (the character) also was Ray's favorite among his many films.
Split into simpler sentences: Many critics and commentators consider "Charulata" to be Ray's greatest achievement. Ray himself remarked that it had the "least flaws" of all his movies, and that the character of Charulata was his favorite among his many films.