Anyway, since George is so similar to Vader, he just needs to be "redeemed" by someone so he can release the OOT. Someone close to him will need to bring him back from the dark side and remember his true self as the director of a movie that was made in the 70's and does not need to look like a film made in the 21st century.
Ah, but Luke wasn't close to Vader. They were virtual strangers. Aside from what intelligence files he could read, and what he divined through the Force, Vader knew nothing about Luke. Almost everything Luke had ever been told about Vader, either by Owen or Ben, was a lie; his sister had met the man, but probably had nothing good to say about the encounter. Therefore, we don't need someone close to Lucas to redeem him, we need a complete stranger who can get in close and influence him. Maybe it could even be ... no, let's not go there.
BTW, if Lucas is Vader, who is Palpatine?