*is in awe of your Peter Lorre icon*

As I recall, Herod Agrippa in the show was presented as charming and likeable, a wanderer between two worlds, with the tragedy of awareness that if he did make a choice, it would set him against Claudius. Which in the end it did. Mind you, the show mostly used him in a Greek Chorus function, offering sardonic if affectionate comments on the goings-on with the Julians; he didn't become active as a character until the last third when Claudius became Emperor, and then it was, after his goodbye from Claudius, of screen.