#1 Customizing appearances of loot and characters.
#2 Statistics (i.e. dmg dealt, healing dealt, efficiency {easily obtained, not reading through a combat log for an hour})
#3 Interacting with the environment, (i.e doors leading into houses, garden walls with private gardens, exploring the city common) also I would like to see some different environmental effects, lightning on an overcast day, puddles after a rain, snowfall in the winter, leaves in the fall)