True, Ye Zun's backstory fits perfectly, but I think it could have been an excellent capstone to the theme if Ye Zun discovered his information was incomplete and took a step back (and then figured out how to redeem himself), because another thing I noticed was that the show was very kind to its former villains as soon as they stopped being villainous. Had they chosen to do so, they could've gone for the "it's never too late to turn back and fix your mistakes, so please do so now" angle. Community service!