They wanted it dark...

Got the DVD from the library. Listened to the commentary track, the director was saying they wanted it all dark and gloomy and raining at the end.

But the cinematographer and postprocessing screwed it up because it can have more contrast and longer shots so you should be able to see what is happening other than shadow fighting shadow.

And they also said something like there is so much they wanted to do for the last AvP fight scene but they ran out of time. WTF! that is the most important scene and should have been completed first!