Not too keen on this idea. Having the predator bashing enemies endless times before they die would really make it seem weak. I don't think that all-out action mode would really suit the feel of the franchise either. Better to expand upon and refine the groundwork laid by Concrete Jungle, I think.
That said, I'd love to see a comic-inspired 2.5D Predator side-scrolling game, evoking the feel of the old AVP games. Something like Duke Nukem: Manhattan Project, but with the focus on hand-to-hand rather than weapon combat.