Here is why some people, like myself, are opposed to the Predator planet-- it takes away the enigmatic mystery of the Predator race. Not only that, the Predator homeworld is said to be too far off from humans to reach, not to mention Predators are NOMADIC in nature. Not to mention, we have seen the Predator homeworld in AvP-R, but mind you a brief glimpse and that was all that was really needed. Granted, what we saw was just one biosphere of the planet, but hey... we saw the homeworld. Not only that, how DID humans find the Predator homeworld, of course that would have to be further explained. The only way I see PREDATORS working is if they somehow did it like ALIEN, only with a group of colonist mistaking the planet for being abandoned and being hunted-- and NOT being traded for technology or forced to compete in a gladiatoral arena.