Penumbra is very funny.

[Brute]

Hmmm... Ok. There is a very creepy and dangerous dog. I have a broom, a hammer and oh, yes, a pickaxe... and maybe a shotgun, full of ammo. What should I do? YES! I risk my life and sneak around him, so he can ambush me easily!

In my opinion, weapons aren't kill the atmosphere. The enemies just had to been more strong, which meens, that they act like the brute. They can kill you immediately and they just make an ourgh! animation by hitting them. You must hit them a lot, when you will kill them.
If Frictional Games would make their enemies like this, weapons are just an emergenty option, which should even been in Penumbra. When I remember correctly, in the first steps of development of Amnesia, should been included too.

Oh. And BTW. I have no idea, why so many people doesn't like the fight system... I found this really cool by swinging an weapon with the mouse, and had no problems with it...