Uh, no advice itself but I feel you on rewriting. I'm converting a fic into origific and just finished the first round with was basically changing the names and pronouns everywhere. I've had to hold myself back a bit because I wanted to change it first before starting the actual rewrite/revision because I know it's easier for me like that.

I don't get bored when knowing where the story goes but I'm sort of exasperated by all the obvious plot/characterization holes removing fandom leaves. It's sort of curious.