Robert Rodriguez's role in making Predators

Sometimes as a Producer, one may have a lot of input on the film. Keep in mind that his horrid screenplay was the template used by Michael Finch and Alex Litvak for their script. It kept the element of an off world hunting ground but that's about it really. And then there are times where a producer doesn't really do much outside of just ensuring the filming is on schedule. Then the name is attached to sell the film. A lot of directors do a presentation of films they didn't make. I.E. Quentin Tarantino, Steven Spielberg, Guillermo Del Toro, Peter Jackson, etc.

As far as Nimrod returning; the first question should be asked "Will there be another film?" I think we can say safely that this franchise is dead in the water. Not since the initial release of the last film, has there been a lot of discussion with a sequel. Rodriguez didn't really seem interested when they asked him recently. More like a "Meh, we'll see" sort of attitude. He's moved on. I think Fox has moved on as well what with studio head changes. I think they want to tread in new territory and leave behind old franchises. Look what happened with Prometheus. I enjoyed the film, but the original intent was it to be a true Alien prequel. Instead they opted to go a truly original path with just a hint of the Alien. Clever. But that's just a inkling of how much they really don't want to bother with either Alien or Predator. It sucks, but I think we've seen the last of Predator and/or Aliens.

As long as the film is good, I don't care who produces it or directs it. :)