Just watched this on a plane, so I missed the apparently great visuals and was left with a pretty terrible script...but it certainly leads to discussion.
My thoughts:
- the black goo is not some universal magic fluid. I think they create many different varities - for any self aware animal - and what was on that planet, at that specific old building, was the Xeno strain. Maybe there was a human strain as well. Maybe many strains. It takes an engineer to swallow the goo and start the evolution process. This was shown at the beginning on an earth like planet. If something else comes in contact with the goo...look out.
- why would they create Xenos? Well, why would they create man? We are no better, just different. Especially to an Engineer. The flaw here of course is the whole 100% matching DNA thing but that was just stupid. Maybe the Xenos have the same DNA also. Maybe that's the point.
- there should be an entire planet of Xenos.
- of course, then the question is why do you need rooms full of Xeno goo. Are they seeding the universe with Xenos?
- David read the walls and knew exactly what he was doing. Why did he poison the guy? Hard to say...because he could? Wasn't that the human's response regarding building an android? But he had to know it wasn't going to be positive, it wasn't done out of curiousity.
- I don't get the WMD/Genocide angle. Where did that come from? I guess from the qty of goo and the lack of contact with humans? Maybe that lack of contact was because of what happened at that facility.
- the movie seems to imply that this was all of the engineers. If there were others on the planet still alive, or a home planet, wouldn't they have come back in the 2000 years to save survivors or clean-up/destroy the mess? This explains why they stopped visiting earth as well.
Or maybe the writers just suck and we shouldn't waste our time thinking more about this than they probably did.