I agree about Johns... His Diana during Darkseid War was pretty good and formidable, but she deserved more of the spotlight in that story. (He and Fabok's portrayal of the New Gods was epic too.) He gave us back Steve Trevor too and a great take on ARGUS that sadly didn't last long.
Johns does such a great job exploring and revitalizing foes too, that I'd have loved to see him work on Cheetah, Queen Clea, Villainy Inc., Doctor Cyber, Doctor Psycho and more.