I'm trying to decide on a new combat mod to replace Deadly Reflex, but I don't know which one to go with. DR is impressive, but DR6 has too many *minor* glitches for me, and DR5 the NPCs dodge too much, and the gore effect only trips for enemies weaker than you... I'd rather have no gore than imbalanced gore.

So, this really isn't meant to be a critique of DR, just a little disclaimer up there so I don't just get a bunch of recommendations for that one. What I'm really looking for ideally isn't a bunch of new animations and mechanics, but a mod that overhauls the combat AI of NPCs so their behaviors more accurately reflect real opponents, instead of constantly running straight at you swinging a weapon while running unafraid juggernauts. Any recommendations?

Have a look at some of Duke Patrick's (spookyfx.com) mods, or, Unnecessary Violence, by Hex_Off.

It's an older one, but I would highly suggest http://www.tesnexus.com/downloads/file.php?id=2073. It makes NPCs more likely to dodge, use power attacks, block or rush at you. I've found that it also seems to help in making NPCs more aware of their health, so they'll run away or back up if they think they might be getting weaker. According to the author's description, it also make guards much more of a challenge.

I combine this mod with MOBs and Kuertee's damage modifiers to get much more intense fighting situations. I tend to die a lot in my games, but it makes me feel like the NPCs are just as aware of what they're doing as I do. If you want to see the latter two together in action, I made a post and video about it for my blog. That would be the second link in my signature.