a straight adaptation of the original Batman v Predator would be amazing. It's probably the best Predator story after the original movie.
Wolverine would be cool, but it would need to be a team of Predators that get shocked by his healing ability. Maybe they accidentally jump to a different universe from one without mutants.
Really, anything like the Hulk or Superman is not going to be entertaining without some sort of depowering. The Superman/Predator stuff was terrible. The original Superman v Aliens was great though. It's just that those creatures are so terribly weak in those universes.
Robocop could be a good one maybe. He's definitely capable of smashing a Predator physically.
Walking Dead is another one I would like to see, or Boba Fett.