Chris Evans could probably do a good Joe Ledger as well. I'd want someone who could nail that All American Soldier vibe, and who better than Captain America himself? The only drawback is that it's almost typecasting on the surface. But I think Evans is a good enough actor to convincingly portray Joe's fractured psyche; the Cop, the Civilised Man and the Killer.
My first thought for Waltz was Syrus Jacobi/Dr Menegle if they adapted Dragon Factory. But again, it's practically typecasting: a super-intelligent Nazi. Nicodemus might be a better role, and I'd love to see Waltz and D'Onferio face off against one another. Both are exceptional. Waltz has two Oscars and D'Onferior has been called, "the actor's actor". Though not an A List star, he is very highly respected by people he works with.
I liked Hemsworth for Bunny because he's usually discribed in the books as a huge surfer bro-type, and that's basically Thor without the Super Powers, lol.