2. The gameplay was repetitive.
Isn't every game?
Not to that extent. The skyhook tracks in Bioshock Infinite at least had different shapes. I'm glad you enjoyed Doom 3 more than I did, though.
It's a FPS, what did you expect? You go in. You shoot monsters or bad guys, and kill the boss at the end.
Even in 2004, there was more to it than that. Wikipedia has a list of shooters that you can sort by release date. Looking at 2003-2004, I see:
* Unreal 2, which had a hub-based mission structure with consistent secondary characters. (I liked it, but nobody else did.)
* Vietcong, which tried to capture the feel of the Vietnam War (and did okay, IMHO). It was also one of the first games to allow iron sight aiming instead of crosshairs.
* Nosferatu: Wrath of Malachi, which I didn't play but I know had randomly-generated environments.
* Far Cry, which had semi-open world gameplay with stealth mechanics, plus a cool setting and okay story.
Going farther back, we have games like NOLF2 (comedy), Battlefield 1942 (vehicles galore), the first Aliens vs. Predator (play as an alien), System Shock 2 and Deus Ex (action RPGs), etc. So there was quite a lot of precedent for shooters being more than running and shooting around the time Doom 3 came out.