Game is really easy, even on Hard... standard aliens aren't much of a threat up close, which kind defeats the purpose - they need several hits to kill you, and before they do you have ample time to either melee (which actually works) or point blank shotgun, as there's close to no acid damage. Even alien corpses.
Shotgun is also very overpowered, as it has sick range and you can easily kill one of them with 2 shots, at worst. Even at a distance.
Human ennemies are more challenging indeed, but I ain't playing an Aliens game to fight humans... Chapters 2 and 3 really were a chore to go through (95% of ennemies are human).
Lurkers are the more interesting foes, as they actually try to hide and flank instead of (slowly) going up to you like standard ones (Drones). But even they aren't really a challenge, as even when they get up close and grab you it doesn't mean instant death - you can mash X and push them away, rinse and repeat.
Ambiance wise the game really picks up by Chapter 4, in my opinion that should have been the beginning of the game.
