It really sort of pulls you out of the story, and lampshade hanging comment about her finding killing to be so easy aside, I think the game would have benefited SIGNIFICANTLY from fewer, smaller, but far more dangerous encounters that required Lara to rely more on her wits than just firepower to survive.
The missions themselves are fun, and a mix of broad base-building exercises and more personal encounters with say, Kerrigan storming through a genetic research lab by herself.