I'm not sure HOW, but I kinda' think that we should either give melee some boosts or drop it altogether. The knife is completely useless, and while the chainsaw can be fun, it's also useless. In one post someone mentioned imitating the "stunning" effect that the chainsaw had in Doom and Doom II. I think that's a great idea, and I don't think it would be overpowered: you'd still have to get into melee range in the first place, and you're only stunning ONE enemy. I dunno.
It'd also be nice to see Doom 64's double chainsaw. As for the knife... I dunno, keep it I 'spose, but at least beef it up a bit. And maybe change it into a rifle+bayonet without the shooting? It'd be more Doom-like than the knife. Wolfenstein might've had one, but Doom never had a knife. However, one of the early Alpha versions of Doom (you can find it floating about on the 'net) contained a rifle as a weapon, and your melee attack was a bayonet, not fists. Maybe spiked brass knuckles of some kind? you can clearly see brass knuckles on the fist of the marine in Doom and Doom II.
Enough melee talk, I got some traits now. I don't think you'd want to implement them exactly as I present them, but something similar... Both are sort of 'fixes' to what I find to be little annoyances.
Calm
Full-auto weapons (Chaingun and Plasma Rifle) will cease fire after the enemy is dead. However, Berserk packs now heal only as much as a small health globe, and do not give the character the berserk effect.
^ I realize that you shouldn't be using a Plasma Rifle on anything that'll die in only a few hits, but it really annoys me to kill something with the first blast, and then completely waste those other 7 plasma cells on the nearest wall. This isn't so much of a problem with the chaingun since 10mm is EVERYWHERE, but it'd still be nice. I mean, when you're playing Doom, you don't continue to hold down the fire button for another two seconds after you've killed your target, do you?
Calculating
When aiming or looking, the explosion range of all barrels in sight are shown. When aiming with a blast-radius weapon (Rocket Launcer and BFG) the explosion range for that weapon will be shown as well.
^ This'll unfortunately cut down on the funny YASDs... But nothing gets me more mad than blowing myself up. It also makes me really mad when I'm gonna take out a group of formers with a barrel, and I end up falling one square short, then they tear me up. Or when I'm trying to blow a passage open without destroying that switch or health globe I'm saving for later... I think this could add an interesting bit of strategy as you could plan exactly where the best place to launch that rocket is. Maybe it'd a two-level, and the first level lets you view barrel range and the second is rocket/BFG range.
Splasher
When aiming a blast-radius weapon (Rocket Launcher and BFG) you may select to target an empty space.
^ Shooting the ground to hit your enemy with splash damage, increasing your hit chance but reducing your damage. I realize this concept is mostly applied to deathmatch, and wasn't widely used until Quake, but you COULD do it in Doom and Doom II, and it's there in Doom III. This could add an extra bit of strategy as well. I've been in more than one situation where if I were allowed to target the floor the splash would've caught an entire group, but targeting the nearest wall or a specific enemy would've left out quite a few.
That's about all I've got. I do have one other little thing, though, and that's red-colored objects and enemies. When the blood starts to fly, it becomes very, VERY difficult to notice these things. light-red objects aren't so bad, but dark-red stuff blends in very very badly. I can't tell you how many times I've been surprised-raped by a Caco because I couldn't even SEE it. I'm sure I've missed some medkits, too. Now, I realize that the red color makes sense for medkits, and Cacos and other red stuff are red in the original games... But can't ya do something about this?
Thanks for your time, sorry I'm so long winded!