To me looks fade, but just about the most attractive attribute any human can possess is an attractive speaking voice. The best part about that is that voices don't change with time!
To that end, Anthony Hopkins knocks them all out of the park. Most beautiful voice I think I've ever heard: he only has to purr 'Clarice' to make my entrails turn to liquid! He also got better looking with age - was quite attractive in his middle age (era of Bligh in 'The Bounty') without being conventionally handsome.
Others with beautiful voices: Timothy Dalton, James McAvoy, Wiggo Mortensen, Christopher Neame, Liam Neeson, Ian McKellan, Jeremy Irons, and the much undersung Bernard Hill. Dalton was abolutely beautiful in his youth. Patrick Swayze too, ditto the younger Victor Garber.
It's a pity Mel Gibson and Johnny Depp have both shown themselves to have such unpleasant personalities. I can see what people saw in Gibson in his youth: Depp, not so much.
As to women (I'm bi!), for me it would be Diana Rigg (another beautiful voice), Lena Olin and Lisa Marie Presley - all unique, unconventionally beautiful, and not like your identikit Hollywood 'star'.
Fascinating thread; it's so interesting what draws different people to others.