Tbh, I didnt like Doom 3, I mean what the hells up with the flashlight?? Gotta carry it, see an enemy, then return fire? Stupid. And it was completely dark, everywhere which annoyed the crap out of me. Which would be half-fine if they could've just had the flashlight attatched to ur weapon, I mean what the hell?
And everything looked the same. I hope Doom 4 is a remake of the original with different looking rooms and setups like the original id games, more lighting, more enemies, less tighter quarters, the original music. And oh yeah, the Doom Marine's face doing the skeptical eye-twitch and bloody face showing ur health level(loved that). 
The idea was to strike a balance between using your flashlight and your gun to add to the game's overall mood and atmosphere. And not every situation in the game was totally dark. The Delta labs lit up quite nicely once you complete the objective of getting the battery back into place. And Doom 3 was already a remake of the original, so that'd be supremely futile.
Well I wasn't feeling it, it definitely made it seem more frightening and mysterious, I'd just like to see the enemy before he kills me and have more around for more action, and I guess I miss the same feel from the originals, the original games on PC were just priceless man. I loved em sooooo much.

I gotta try out Resurrection of Evil though. I always forget they were different.