Avatar strength. AKA, player levels. Now, don't rip on me because of that, because there are a couple games that I really enjoy with different levels, but come on... should it seriously make a difference to slice a skeletons that is level 1 and to slice the exact same skeleton only when it's at level 10? They are made up of the same stuff at the same thickness. They're somehow way loving different because one is higher level. Levels make games so forgeted up. I can see getting skills like strength, but forget, make them proper. Don't make it so if you have 5 strength more that you decimate an enemy but somehow swing at the same speed. If you have more strength, you're going to swing a little loving faster.
Also, being able to carry 4 sets of armor. I hate how terribly unrealistic most inventory systems are. It's not just a little overdone, it's way overdone.
Oh, and bad hitboxes. (CoD)