I love Brutal Doom. It's like if you took three servings of Doom, put them in a blender, turned it up to the "RIP AND TEAR" setting, put the result in an ice cube tray and froze it, smashed the ice cubes into dust, and then snorted it off a dead pinky's backside. Intense, messy, and absolutely satisfying.
I find pretty much everything from Xaser and Weasel to be enjoyable, of course. From Psychic to Diaz to Grenades N' Stuff to Cold Hard Cash (GASP, AN *EDGE* MOD!?
speaking of which Immoral Conduct is still one of the best ones out there, albeit somewhat primitive by today's standards. Then again, this is DOOM. *EVERYTHING* is primitive by today's standards.
), it's all good.
I would say "AEons of Death", but that's not really an "enhancement" wad; It's a completely different experience.
Hideous Destructor still holds a place in my heart, even though I suck at it. It's right around that level of unfairness known as "Nintendo Hard", which is hard enough to make you throw down your controller (or keyboard in this case i guess) in disgust, but not hard enough that you won't try it again. I wish it was compatible with Skulltag, though, because I'm sure it'd be a blast in Survival. Except nobody would ever host it in Survival BECAUSE THEY'RE ALL PUSSIES.
Actually, you know what? I'm going to stop now, because if I listed every mod I liked, I'd be here all day. These were just some of the first ones to come to mind, so don't be offended if I left yours out. I'll just leave it at this: I've never played a Doom mod that I wish I hadn't*, and I've tried quite a few of them.*except UAC Military Nightmare but that hardly counts. The GVH-knockoff version of it was... interesting, though.