Hm, just met Clancy at work last Monday. Not really the kind. Phillipe had the best overall auditions, but Natlie er, reacted favorably to Hayden let's say.
(An aside: Poorest decision was not bringing Haley Joel Osment back in in '97-'98.)
In '77... who did I picture and who is the equivalent? I think I pictured, then, someone more like Harrison. In '77 no one knew he needed to fit the suit. And a character more like Fett: subtle, but always aware. After '83... Mike Biehn's too small at just 6', but someone a bit more like Reese could have been interesting and his looks probably would have worked.
For a prequel I'm afraid I don't know enough about contemporary actors. And I can't think that anyone at mid-twenties could do the work. I like the Caviezel notion, but for reasons mentioned, it wouldn't have happened.
I think his turn should have been some perversion of a Jedi test. Where most turn away from the temptation of the dark side, Anakin misunderstands and embraces it, thinking he is strong enough to move through the trial, but once he's in the Emperor can sense and control him.