I liked the performance and thought Ben Mendelsohn was acting his ass off...but undead Peter Cushing and the big man stole every scene they were in. Krennic seemed very much in over his head when compared to those two, and I think that was maybe deliberate. But I also suspect there were scenes of his that were cut or reshot which may have effected things. But in terms of where I'd rank him? He's right in the middle road of the series villains.