Remember, some fo these mods require either Tribulan exp, or Bloodmoon exp, sometimes both...
Better Bodies
any head replacer mod (not a name, but a what you should search for.
Faces Of Vardenfell (sp?) is good starting point)
Japanese House mod (by sniper daria)
Real Katana mod (by Karstux.
http://www.apoapsis.net/ )
Horror Mod
Morrowind Comes Alive (latest version)
Giants Ultimate (by Puma man)
Wilderness 2 (ADDS ANIMALS AND BUGS AND OTHER WILDLIFE TO MORROWIND!!! By Puma Man)
Wilderness Sounds (above. Adds ambient sounds to morrowind)
TLM Lightning Mod (enchances power of lightsources and makes dungeons very dark. Makes torches and lights more needed. A real atmosphere enhancer!)
Assassins Armoury
TESTOOL (after installing mods, use this to fix most compatibility problems and fixes leveled lists so you wont get any lvl50 monsters when in level 1
. just press JUST FIX IT button)
Non-mod like:
Morrowind Visual Pack 2.11
Morrowind Visual Pack 2.2 Nature
Visual Pack XT (install in this order. makes world textures MUCH MUCH better! There are others too, but you can compare them here. Pick your favourite. Really makes morrowind look better.
http://ltm.ufrealms.net/textpacks/ )
A Darker Feel Music Mod (by Narcoza. Gives morrowind much more variety to musics. Good stuff!)
Most mods are available here
www.rpgplanet.com/morrowind