It's hard to decide P1 or P2, I like both for different reasons.
In P1 the Predator was a deadly mysterous creature from outerspace and the cast/action was awesome.
P2 gave us more Predator. We see him eat, more of him uncloaked, more indepth medical repairs, more Predators at the end, the ship, the trophy case...a few examples. Sure we also get this with Predators, just not too fond of the SP's yet.