A minor gripe when playing Call of Duty: Black Ops II: piloting the aircraft at the end was difficult when chasing down the drones unless you turned up the mouse sensitivity.  That's not huge, though, because I could work around it.

What I found unforgivable was the multi-minute intro to not only each campaign level, but often the beginning of each section of the campaign level.  The insult to this injury was the several cinematic portions where you lost control.  Games should always have skippable cut-scenes and sections when gameplay is gone.  I shouldn't have to wait until a minute (or more) into the cut-scene.