Freddie Mercury. He did rock/pop to perfection. No one did it 'bigger'. He could have sung opera. Anything really. Personally think he is head and shoulders above all the rest
Paul Rodgers is up there in my opinion because he can still do it.
Robert Plant was up there in my opinion but he has lost almost all of his former range.
The real conversation ender is probably Pavoratti but I don't know enough about opera to say. Maybe Caruso but there are no recordings that can actually demonstrate his talent as they are all crude and tinny.
