Without giving too much away, note that the game features a civil war between Imperials and Stormcloaks. Also note that the soldiers fighting in said factions are poorly equipped for battle. As the developer points out, the Stormcloaks are literally wearing the worst armor in the game. This mod fixes that.
In a nutshell this mod outfits the soldiers in each faction with better gear. For instance, you'll notice Stormcloaks with Steel or Scale armor.
You'll also notice Stormcloaks with improved shields. You'll also start to notice a difference between Imperial soldiers, archers, heavy units, and Officers. It's an excellent improvement over the vanilla game and the variety it adds is noticeable.
The developer plans to expand the mod to cover the hold guards but it's unclear when this update will come out.