In this thread, @kingpotato and I were talking about things we would like to see improved on in the next Elder Scrolls game, and we got to talking about how in Skyrim, you can't fight effectively on horseback, and your "warhorse" doesn't fight unless you dismount.
How the devs didn't think to make your horse ... useful ... in combat, is beyond me.
What are some stupidly obvious things developers have neglected in your favorite games?