A bundled kinect could be a good thing.
A lot of games could still be played with a controller and detect gestures for smaller things, i'm always bringing a couple examples like:
Forza 5: playing with a wheel your hands will be displayed in cockpit view mimicking your actual hands placement and animation.
That would solve animation issues (game could finally show you turning the wheel lock to lock, correctly display when you take one hand off the wheel to shift gears etc) and even allow for nice hand/arm gestures when you overtake an opponent
Halo 5 or fps in general: when you take your hand off the controller your arm is tracked, which allows you to communicate with people in your team through gestures or mock your opponents. Or launch grenades the way you want: throw them in every direction, distance, elevation. Make them roll on the ground, or simply drop them at the opponent's feet and run away. Throw a grenade behind your shoulders when you're being chased without turning.
In general, the controller should have some very simple sensor to detect when you're holding it with both hands, with just one hand (left or right) or you've dropped it altogether; when you take one hand off the controller, your character 'exits' its default 'pose' and your arm starts being tracked instead
That would work for most FPS, being able to move both arms in front of you and use them in different ways.
In Far Cry 3 you'd take your hand off your gun (or won't if it's just pistol or anything you can operate with a single hand) to make your way through the foliage, move leaves blocking your sight.
Or waving your hand in front of you to make flies and insects go away
Even better if, in addition to sensors, the controller was made of two detachable parts you can easily link and unlink during gameplay; that would allow you to use gesture to a degree without having to take your hand off the controller and your thumb off the left stick; like using your left hand to move a curtain in front of you and shoot with your right hand.
Also, full head tracking for fps. If it's responsive enough and combined with 3d that would enhance the experience tremendously. Moving your head and body and seeing the pov changing accordingly would be amazing, finally being able to lean on corners etc.
http://www.youtube.com/watch?v=Jd3-eiid-Uw (skip to 2'50")
attempts at this with kinect 1.0 were too unresponsive and not accurate enough (FM4 autovista) to work, but maybe kinect 2.0 will make this possible.
