Immersive Citizens - AI Overhaul 0.4

Vanilla Skyrim has a variety of issues. Most would agree that the passage of time has not been kind to it, with a ton of people rightfully pointing out a ton of issues with it. Luckily, Skyrim has one of the largest modding scenes around and a ton of creators have dedicated themselves to fixing the game's many issues. One of them is Immersive Citizens - AI Overhaul, which focuses on overhauling NPC behavior to make them feel like living people.

To install the Immersive Citizens - AI Overhaul, drag it into the Skyrim Data folder, as well as using LOOT to determine the optimal load order so you don't crash your game constantly, much like most Skyrim mods. Alternatively, use a mod manager like Vortex to install it for you.

This mod is one of the most ambitious mods out there. It's goal is to reprogram every NPC in the game to react like an actual human being would. So when a dragon attacks a small village, you won't see the villagers rushing at the dragon with fists out ready to defend their home, they would run away and hide. This is part of a new "Survival Instinct". Outside of combat, each NPC now has a schedule and will occasionally travel and respond to the world around them, depending on the individual's profession and relationships. 

This mod is so great that it's been officially featured by Bethesda themselves. If you want to improve your immersion, then you should definitely give Immersive Citizens - AI Overhaul a download.