Erastus was in the top-1000 several times at the end of the 19th century, but it hasn't been on the extended list since 1957. Erastus of Corinth is mentioned in the Bible as an early Christian, and there were several famous Americans named after him in the 18th and 19th centuries (railroad magnate Erastus Corning, university president Erastus Otis Haven, etc.).
I don't think Erastus has quite the comeback potential of Barnabas or other early Christian names. It sounds too much like medical/sexual words like estrous and masturbate.