The more I read about him, the more I’m convinced that it was Hadrian who fused Greek and Roman culture and made it the cornerstone of Greco-Roman/Western civilization.
Either way, I think Hadrian is one of the most underestimated Roman emperors. To my knowledge, there are only two modern, scholarly biographies of Hadrian (Bernard Henderson in 1923 and Anthony Birley in 2000). Perhaps it is my calling to write a third biography (so around 2019, check out Amazon ;D).