I enjoy the game, but I think they made PCs too hard to kill. I've been playing for 8 months, and DMing for about 2, and I don't think I've ever seen a PC in real danger. It's starting to bother me, and I could see this eventually turning me off the game completely. Success is boring when there's no chance of failure.
This is bothering me somewhat too. We've only had two deaths, and one of those was collateral damage from a fellow party member's spell. While we've occasionally had some dirt naps, they don't happen often, and it's almost always the defenders. I don't think the Warlock has dirt napped once. Even then, there's never been more than one failed death save.
And given Raise Dead, even if they die it's not that big of a deal.
I have brought in a house rule with 75% hp and a dmg bonus equal to 1/2 the monster level.