Morrowind Graphics Extender:
This tool allows the user to modify the game files to allow settings like increased view distance, widescreen resolutions, and various other visual tweaks.
This mod replaces the awful body meshes and textures from the vanilla game. Pretty much a required mod, IMO. Just be warned that this mod can include nudity if you configure it that way. Make sure you use the underwear version to keep it PG-rated. ;)
Companion to the Better Bodies mod, this mod redoes the common armor and clothing meshes and textures to better fit the new bodies.
More Better Clothes:
Same as above, but adds the rest of the clothes that were previously missed.
Passive Healthy Wildlife:
This mod makes normal creatures, except those that are supposed to be aggressive, leave you alone unless you provoke them. Diseased and Blighted creatures still attack as normal. Sick of Cliff Racers? Get this.
HELLLUVA WICKED WEAPONS:
This mod adds a TON of weapons to the game (apparently over 1500!), including my personal favorite: the Daedric Crossbow. Sure, they may not all be balanced, but they sure are fun!