One more thing I want to add to my list:
11) Origin Story - Give John his definitive origin story. I would make it as streamlined and cinematic as possible, like him becoming a GL is a big deal (this time with better art, lol). I would also keep referencing it to show how that turning point in his life shaped/changed him and use it to flesh out the "Opener of Doors" prophecy later on. Basically, I want his origin to be memorable, iconic, and vital to the character.