Today I made a mini AVP marathon - "Alien Vs. Predator" DVD, "Alien Vs. Predator: Requiem" DVD and "Predators" BD.
AVP:R was so dark, that I was forced to change setting from standard (calibrated) to dynamic (brighter-than-sun) to be able to discern something - anything - in many scenes... image sometimes lacked details, at the contrary of AVP that was astonishing for a DVD.
About color grading, the first shot - which is the same from the end of AVP - has completely different colors, while the rest of the movie seemed ok to me - it could be interesting to apply a color regrading to the first shot, to be equal to AVP color wise, and see how the whole movie looks like.
Don't know if the BD of AVP:R has the same problems - brightness, *possible* color grading problems, low resolution - but if it is, it has a chance to be a future candidate for a preservation... don't you think?