I like it
And even though I'm not a fan of the AVP series. It sounds like it would keep to the mythos of the Predator "Culture" (I'm an Alien fan so I'm not very versed in their lore)
At first....I thought it convenient that there would be "Aliens" on the Planet that the survivors escape to. Then it occurred to me that the space station would be close if they had located a Hive on it. And were monitoring it from space...collecting skeletal remains (as you suggested
)
Good luck with "fleshing" out the story
What I would like to see(this is just my preference...its your story idea
) that it is more about survival of the species. Now which species...Humans...Preds...or Aliens? All would be fighting for their survival. And all would be fighting each other(not necessarily at the same time).
But not to just focus on the Alien vs Predator. The first AVP had more character development the the 2nd (IMO). And in an AVP movie the characters are the Preds & Aliens but if there are gonna be humans. They should be characters that one can root for. So maybe my idea would be Humans vs Aliens vs Predators. The real battle is survival