He has many flaws, in the sense that he is excessively aggressive, revenge seeking, etc.
Replicants are emotionless biological creatures created by humans. Emotions are what describe and classify human beings. Man cannot create something as perfect and pristine as that what God creates. However, replicants are able to eventually develop some emotions
Victor views Frankenstein as a failure and a monster and tries to escape it's wrath. In addition, his grotesque, inhumane features cause others around him to consider him a deadly and dangerous creature - DeLaceys, father of drowning girl
Humans view the replicants as if they are of lower value and status - they enslave them, and eventually when they rebel, the replicants are viewed as monsters and sent to another planet, making it illegal for their existance on Earth. They have a law to kill any of them that live on earth
These creatures could be more human than us - Frankensteins desire for companionship and friendship. He confronts the Delacey's in a friendly manner, but they chase him away like wild animals, Roy the replicant saved Deckard's life, even though he (a human) was trying to destroy the replicant race and life form on planet Earth - showed they are just as, maybe more human than we have ever been