Taleworlds created the most unique and what was widely considered the best melee combat engine in gaming.
Bethesda took a tired, old idea and gave it a shiny coat of paint.
Mount & Blade, in a better Engine, with better quests, a better Endgame and more interaction, would be perfect. It doesn't need a complete overhaul. It's simplicity made it appealing - Hell, I am still playing Warband today. They found a good formula with M&B and made improvements on it with Warband, With Fire And Sword and Napoleonic Wars (Which, James, does have crouching).