I haven't played it in ages but I'm not surprised the game looks old but doesn't feel as terrible to look at as it should. Something about thinking of imperial facilities being drab and blocky makes the visuals just sort of "fit" and probably age a bit better than they wold have otherwise. And I remember LOVING the audio. Seriously to this day the sounds of blaster fire put a huge smile on my face.
Yeah, the atmosphere in Dark Forces is great. It definitely makes up for the otherwise dated visuals. And I have to agree, the sound is awesome. The sound effects really help to draw you in and the music is top notch.
On another note, I am now playing Dark Forces II. I have so many stinking memories from this game. I love it. It's weird, too: I haven't played it in ages, but because I played it so many times when I was a kid, I instinctively remember where almost every enemy is, at least in the first couple of levels. There were a few times where I would be running down a hallway and as I passed a turn or a little niche, something would tell me to face it, and lo and behold I would see an enemy. Also, I don't care how cheesy they sometimes are, those cutscenes are the best.