Homework fosters learning and shouldn't hamper personality development. Children need to learn outside of a classroom setting, otherwise parents simply train them to learn in just one particular area and not outside of school. Learning happens with every breath, not just at school. Homework doesn't dampen personality development--it makes students better lifelong learners.
There is no reason to believe that homework some how hampers personality development. Everything a person does helps to sculpt and mode a person's personality. Taking part in an abundance of activities including educational activities is good for a person and their growth. The amount of homework a person has will not significantly impact their personality.