Criteria: Realism of Atmosphere Added, Amount of Added Content, and Level of Darkness.

Skyrim Darkness Immersive Corpse by C0331

The visuals this mod adds seems so fitting. Skyrim is a harsh land. But yet no one seems to have died from the harsh climate.....that's weird. This mod adds some fun sight seeing along your journey. Further, you'll be treated to journals full of the deceased's last words for some added immersive stories.

Immersive Fallen Trees by Jurassic4LIFE

Much like the Skyrim Darkness Immersive Corpse mod adds dead bodies, this mod adds dead trees that have fallen over in various places. Just like the above mod adds corpses that have fallen to the harsh and cold environment, this mod adds trees that have fallen to the harsh environment. In other words it makes Skyrim look more dead and therefore fits in nicely with our list. Also, some of these fallen trees conveniently function as bridges.

Artwork by GhostAgent

Justice - City Exteriors by GoodfellowGoodspring

This little addition makes for some nice site seeing. The main cities are now adorned with caged criminals baking basking in the sun while many stop by to admire them. In a harsh land, public shaming comes complete with drownings and very fine details that hint at possible decapitations and limb dismemberment! This is to the world of Skyrim what Rembrandt is to the world of art--a true masterpiece indeed.

The Honored Dead by jakeoberg

Hurray for dead people! Dead people everywhere! This happy little mod adds dead soldiers throughout the land to remind you that there is a civil war in place. You can stumble across remains that hint that a battle had taken place nearby, as well as see conquered foes hung on display for all to see. This mod is very much like Skyrim Darkness Immersive Corpse (listed above), but focuses more on the civil war aspect.

NOTE: Some have posted that the hanging bodies end up falling down. Many think it is due to an incompatible skeleton mod, but it has been pointed out that no such incompatibility exist. It is simply Skyrim's engine being weird as usual. So if you your hanging bodies fall, just assume it is because the noose loosened over time and gravity did its thing.

The Immersive Dead by FalloutTimes

This is very similar to the above mod and focuses on the same aspects (the civil war), but instead of having corpses spread out in various places to show a battle had taken place, this focuses on the actual military camp, plus throws in animals. So while venturing into an imperial or Stormcloak camp, you'll see coffins along with dead animals that one can presume is being kept for meat--all in all a nice touch.

Bring Out Your Dead by he that needs no introduction, Arthmoor

A tidy little mod that adds proper burial for those poor schmucks that get in the way when dragons and vampires clash with epic heroes. The mod expands the burial grounds (graveyards & Halls of the Dead) within the game so that when (notice that we didn't say if?) unique NPCs die, they will be respectfully buried. This serves as a permanent reminder that you, have failed miserably in your duties....some Dragonborn you are.

Public Executions by lordkoz

Well sheesh! This mod totally fits in with this list. Remember the first execution you witness in Solitude? (If you are new to Skyrim, and have not yet entered Solitude, forget you just read that.) Yeah? Wasn't it cool? Yeah? Well this mod author thought so too! So he recreated the scene. Now brigands are always being decapitated admired by all surrounding onlookers. Now you can bring your significant other along with you to Solitude for a romantic evening show. Bring the popcorn!