I like the idea of shared universes. Blade Runner, Outland, Event Horizon - they seem to fit really well together even if they're not supposed to.
I like the idea of the Xenos and Yautja inhabiting the same reality - though cinematically it hasn't worked that well (that said, I'm a fan of AvP, it's one of my favourite films, but I do understand the detractions).
But, as much as I liked it, AvP stories really should be set in the future - setting them in present day just doesn't work. Predator only - yes - that works, but including the xenos has spawned a zillion pages of canon arguments that should never have happened.