I posted my opinions several times before about DOOM 3, but if there's one thing I think I never mentioned is that one thing I missed the most while playing it was open outdoor areas in the veins of DOOM and DOOM 2, along with more enemies on-screen. Instead they went "reboot" mode, added some context-related realism (it's Mars, going outside would kill without a proper suit, etc), confined most of the game in small indoor facility areas with very few outdoor glimpses and fast, urgent outdoor trekking to reach point 'b' (I remember a part where we go outdoor but it's very limited by lack and constantly decreasing oxygen in the tank, or something like that). And all that in visually-repetitive maps since you're playing most of the game in the same facility which itself is of course not going to look different all the time you get to a new "map".
Additionally, at the time of its release (and months later if not years) DOOM 3's lightning and shadow system was top-notch, unequaled in the gaming industry, and id Software showcased it "best" by confining the game to indoor environments because of said lightning and shadows system (otherwise making the game in bigger environments wouldn't have had the same impact). In fact I often wondered if id Software went "corridors, darkness and put that flashlight on the gun" mode for DOOM 3 because they wanted to showcase their new engine, you know... rather than making DOOM 3 as it was because instead they wanted to make it as it was out of actual will to do so and with passion thrown in as well. In other words, you get a new engine capable of "this and that" with lightning and shadows, but you don't know where to go with DOOM 3, well then the best thing to do is create a "game" out of the technology you got, rather than creating technology based on the game you want to create... if that makes any sense.
I can definitely understand why some (perhaps many) gamers really liked DOOM 3, but the main issues I referred to are the ones that really got on my nerves for most of the game. The last couple of maps (the 'Hellish' ones) get much better and have a better "DOOM feel" to them but they're still relatively confined... heck I think that the biggest area in the entire game is the last room against the Cyberdemon (and if not then the largest room in the game most be of similar size anyway).
I was just expecting to blast through 20, 30, 40+ zombie marines, demons, barons, and good ol' Imps while having an big indoor or a large outdoor area within which I can strafe non-stop and avoid slow-moving Imp fireballs. But then I guess that would have been "just remaking DOOM" in HD? Well, yeah that's what I want. I hope that DOOM IV gets back to the classic DOOM roots. I guess that DOOM 3 had some spooky moments, sure, overall it was dark, some places had nicely scripted/triggered flashing lights and sudden sounds and critter roars in the background, seemingly coming out of a vent or some door you just passed by. Things like suddenly seeing some fast-moving shadow going by a window of another room you have to go in... but that's a bit old in my opinion (I.E. similar scare tactics don't get me anymore). I did get some few genuine "jump scares" but very few since I actually expected most of them after maybe two hours of play, and just eventually kept running around to the next objective whilst becoming almost oblivious to the triggered horror game-play mechanics that were supposed to stop me in my tracks.
This is perhaps ironic though... because I do believe that back in 1992/93 (before, or during DOOM's development) due to technology constraints, or rather not constraints but simply the technology available at the time (period) convinced id Software that DOOM could not be a focused-on-horror elements game (for example) because graphics at the time wouldn't have made it convincing or immersive enough), and that might have been why (speculating here) we've known DOOM the way it is now. Rather than (for example) having id Software creating DOOM for the first time ever in 2004 instead, the way DOOM 3 was created, because then at that point the technology was there to make the original DOOM that they "always wanted to create from the start". As a matter of fact DOOM 3 is a reboot (obviously the '3' in the title kept the hype up alright), which of course leads me to believe that id Software experimented with DOOM 3 and actually took a considerably risky gamble by going "the way we [id Software] always wanted to do it back then", rather than giving us a DOOM 2 HD.
But anyway... they supposedly want to make (or are currently working on) DOOM IV. Well, honestly I don't know what they'll do with it since I don't quite know where the franchise can go now. A "sequel" to DOOM 3's events? Perhaps... if not... a re-re-booted DOOM again? Who knows... will it stay on Mars with the good ol' "you're alone against all odds and Hell" formula? Or will it go the modern shooters "you now have a squad and you cleanse the streets of modern day New-York with all new-to-the-franchise DX11 effects showcased in this nice cityscape" COD-style route?
Time will tell...