Here's a list of little mods that don't seem like much but make Vvardenfell a place more alive, improving your immersion. You'll find a lot of animated models as well as ambient sounds and a few voices (unused voice files from the game).
You won't find mods that add clutter, or improve on landscape or cells. These may very well add immersion but are out of the scope of this modlist.
Whenever possible I have added a video, gif or image so you'll be watching a lot more than reading here :D
Glow in the Dahrk by Melchior Dahrk
One of two graphic mods I'd recommend no matter what. Standing outside at night, see light through windows. Standing indoors during the day, see the sunlight shine through the windows.
Just Drop It by Merlord
The second must-have mod. You'll want this. In Morrowind, any object when dropped will always be perfectly vertical, no matter where you drop it, resulting in a game of balanced stones. With Just Drop it, an object, or a corpse will fall ALONG the floor
Graphic Herbalism by Stuporstar and Greatness7
A new re-write of Manauser's legendary mod. Activate the plant to harvest parts of it, what's not picked up stays. All that, without adding scripts to the plants and therefore without conflicts.
Weapon Sheathing by greatness7 &al
See weapons carried by npcs and the player, carry shields on the backs, and auto-add quiver when arrows or bolts are equipped. A mod that made Morrowind more modern just like that.
Vanity by Abot
We dreamt it, Abot made it! When the player or an NPC wear a ring or an amulet, the ring and amulet will be visible.
The Midnight Oil - Lighting Overhaul by Merlord
Quite simply this mod lets you turn candles and lanterns on and off. In addition, when a candle or a lantern runs out, you can refill it with a new wick or more oil. That's not all, your lanterns and candles will not go poof if you accidentally go into the water with them. Lanterns in town are off during the day, and on at night.
Pincushion by Hrnchamd or N'wah Shooter - Marksman Overhaul by AxeMagister
Either mod will let thrown projectiles (arrows, bolts, throwing stars and knives) stick to the surface they hit.
AxeMagister's mod also lets you retrieve the arrows and comes with a number of gameplay features.
Swayland by Wazabear
Animates the rope bridge to sway gently.
Heat Haze by Vtastek and Tewlwolow
When you get close to lava pools, you'll see a subtle heat haze effect.
Unto Dust by Melchior Dahrk
Adds a subtle cloud of dust in tombs.
Dwemer Lightning Rods by Melchior Dahrk
If you are near a Dwemer tower during a Thunderstorm, you'll see the tower being hit by lightning.
OAAB Saplings by Melchior Dahrk
In addition to your favourite grass mod, use Saplings. Personally, I use them to generate distant land but don't activate the esp, much like grass mods.
Adds glowbugs to the Bitter Coast and Ascadian Isles at night.
Adds mist to the Bitter Coast at night and in certain weather.
The Blight by OperatorJack and Greatness7
NPCs, plants, creatures and the player will visibly look ill when infected with a Blight disease. In addition, the blight can be transmitted from and to the player, npcs, plants and creatures.
Fallen Ash by NullCascade and Greatness7
After spending time in an ash storm, the player will find themselves covered in ash. This applies to npcs and buildings as well!
Nocturnal Moths by R-Zero
At night, see moths flying around lanterns.
Cave Drips by R-Zero
See and hear drops of water fall into bodies of water in caves.
Flies by R-Zero
When you find a dead hero, you'll also see and hear flies above it..
Enlightened Flames by R-Zero
In vanilla, the flames of a candle are always aligned with the candle... even if said candle is tilted sideways. Now, the flame will always be vertical, no matter how the candle is positioned.
Throbbing Meat - a Corprus Meat Replacer by R-Zero's
It's gross, it moves. You'll love to hate it.
Shattered Stones - An earthquake mod by R-Zero
While exploring the Ashlands, Moalg Amur or any volcanic region, you'll have the chance to hear an earthquake with a screen shake effect.
Silt Strider Animation Restored by R-Zero
This restores an unused animation for the silt strider. You have 50% of seeing the one you've always seen, or the new(found) one.
The Dream is the Door by Melchior Dahrk
During the main quest, you'll find a door, when you do, you'll see the magic.
Parasol Particles by Melchior Dahrk
The Emperor Parasol trees from now have a subtle particle effect that completes their look as very large mushrooms. Comes with compatibility with Peterbitt's replacer.
Keg Drip by Melchior Dahrk
Kegstands now have a liquid dripping from their taps.
Vapourmist by Tewlowlow
Adds dynamic cloud and mist to your game, based on the region and the weather.
I Lava Good Mesh Replacer by Melchior Dahrk
Beautiful moving lava. Also seamless.
Morrowind Animated Hammocks by Vegetto
This hammock replacer makes the hammock sway a little
Salts by Hater8
It doesn't look like much but with this mod, fire salt, and frost salt finally look magical.
Visually Filled Soul Gems by NullCascade
Filled Soul Gems have a magic glow like enchanted items do. If you replace your enchanted items magic glow, that will be used for soul gems too.
Crystal Soul Gems by SVRN & Spacedevo
Gorgeous retexture of soul gems. Multiple versions to choose from: with/without glow, with/without particle
Improved Propylon Particles by Starwarsgal
This one might be a matter of personal taste, but I've always found this replacer a lot prettier and more mysterious that the vanilla VFX.
Aura by Tewlwolow
Aura adds all kinds of Ambient sounds, weather sounds, and even voices. You can customize what you want to hear directly from the game menu.
CSO - Character Sound Overhaul by Anumaril21
Footstep sounds change based on terrain and based on boots and new sounds for menu interactions (weapons, armour and items) are the major features. More, and naturally, you can tweak to your heart's content directly within the game.
Voices of Vvardenfell by SombreNeri
A subtle tweak to many voice files, including Daedric Princes.
Heartthrum by RedFurryDemon
This is so subtle but so powerful: as you get closer to the Red Mountain and to the Heart of Lorkhan, you can hear it beating louder and louder. No video but trust me, you want this.
Loading Doors Lock Tune by Abot
In vanilla, you activate a loading door (i.e. a door that takes you to a different cell), the open door sound plays, game loads... and voila. With Abot's mod, a few second after you enter a cell, you'll hear a closed door sound too.
In addition to this, locking a door will also lock its corresponding door. In vanilla, a loading door is in fact two linked doors, each of them has its own open/closed/trap setting. Now the open/lock is synchronised.
Ambient Town Sounds for Morrowind by Lendrik
Adds people/town sounds to settlements. Even better if you have an NPC mod such as Friends and Foes, Starfire's NPC additions or MCA.
Tunnel Cough by R-Zero
Miners cough from time to time. That's all.
Store Entrance Chimes by R-Zero
Whenever you enter a shop or tavern in an Imperial settlement, you'll hear the store entrance chimes. You can also see the bell hanging just above the door.
It's a Deal by Von Djangos
Traders will now thank you for doing business with them with a voiced line that was shipped in the game but wasn't used.
FMBP - Greet Service by PoodleSandwich
Traders and service NPCs will greet you properly, using voiced lines from the game as well as new spliced lines.
Idle Talk by Von Djangos
Similar to the previous two mods but this one applies to any npcs. Using unused lines and/or edited original voice files, npcs will react to your faction and will comment on things of interest to them.
So. You're the Nerevarine. by Vehkofficial
In the same vein as Idle talk, using unused lines from the game, more npcs will comment on you being the Nereavaine, once you are the Nereavarine.
Voice Overhaul by Phoenix Rime
Very similar to Idle Talk but focuses on races other than Dunmer.
Haunted Barrows by Melchior Dahrk
Gives the Nord Barrows in Silstheim their own sound. The game normally uses the same whisper sound as tombs.
Sea of Sounds by Cpt Joker
As you get closer to a body of water, you'll hear the new water sounds. Includes new waterfall and underwater sounds.
Water Sounds by Abot
Many mods, chiefly Tamriel Rebuilt use "water meshes" to create rivers. The water meshes are not water, so walking on/through them makes no sound. Abot's fixed this.
Silent Assassins by R-Zero
Dark Brotherhood assassins won't taunt and grunt as much during combat. They are supposed to be silent deadly hunters, after all.
Sound Spell Sound Effect by R-Zero
When under the effect of a sound spell, you hear a sound. That's all.
In the same vein, I loved the spell effect for Blind in Magic Diversity Complete. You'd get a purple cloud of smoke on your face effectively blinding you for a few seconds. Sadly, I didn't like some of the other effects and the new sounds.
Thunder and Lightning by Abot.
A remake of Jac's Lightning mod. During stormy weather, you will see lightning bolts, you might even get hit by one.
Thunderstruck sound replacer by Mouseplay
A simple sounds replacer, but a good one :)
Sounds of Souls by NullCascade
When near a filled soulgem, or if you are carrying one, there is a chance you will hear the poor captured soul moaning. Creepy. Perfect.
Sheep no more by McChuggernaut
In the game, for a mysterious reason, you can hear a sheep in the Ashlands. If that breaks your immersion, this is the fix. Another solution is this mod: The Story of Shaggy the Goat by Nerevec that makes the sound of sheep make sense.
MUSE by Rytelier
Muse lets you customise the mp3 played when you explore and when you fight. You can determine a playlist per region, per town, per cell, per enemy even.
Personally, for a most immersive game, I like to remove all music for exploration and combat, keeping music when I am back in town only.
That being said, we now have lovely music packs tailored to specific regions and cells if ambient sounds are just not enough. (see the Requirement section on the MUSE page to see all the music packs).