My favourite is David Coverdale in about 1980, but I think George was better looking than Paul. Middle-aged Paul was quite nice looking in a sort of everyman way.
But he's a bass player, not the frontman/singer so not sure he's allowed to be counted.
Do you have to be a singer to be considered a "star"? I'm not convinced. I'd actually take issue more with the description of Paul McCartney as "rock" - isn't that style considered pop rather than rock?