Played around with interesting new concept for mouse control over movement.
1) You have stopped.
2) You are looking and facing straight forward.
3) You start to move the mouse -> your eyes move.
4) The crosshair is in free movement mode and the view follows the mouse only slightly.
5) You can target things which are in the middle region of the screen. Crosshair moves around, the view mostly doesn't.
6) You start to move the crosshair over the threshold -> you experience very slight resistance and your head starts to move.
7) Head catches up with the eyes. Crosshair does not snap into center of the screen, rather the view snaps to the crosshair.
8) Head has some 45 degrees of free movement in all directions.
9) After crossing the 45 degree threshold you experience small resistance and the body turns.
10) Body rotates in small increments.
11) Any movement like walking, running, etc snaps the viewport to crosshair.
12) If you look at direction X for a while you will be "zeroed out" in that direction, making that the new default direction and the head and body rotates to face that direction along the horizontal axis.