I hope they go really macabre with a Predator lair if that cave is his makeshift lair. If anyone read the original Predator script, Dutch stumbles upon the Predator's hunting camp it has set up. Predators '10 took this idea but one element none of the films have touched upon is what the Predator does with the skin when it flays it's victims. This was from the original script;
"Schaefer starts after him but then stops, dumbfounded
by the incredible images that crash in on him:
TRANSLUCENT HUMAN SKINS stretched over frames, the hair
of the attached scalps moving lightly in the wind;
SKINNED BODIES, some lying on the ground, others hung
from the trees, like Hopper and his men were."
I wouldn't mind seeing something like this just to show how cruel and sadistic the Predator is.