Great mod mate!
Is there a way to move the cam in free mode so we can alt+Num7 areas of the map as hangar not accessible via tanks?
Short answer: No.
// switch freecam in hangar on and off:
"freecam": "LSHIFT F3",
No, he meant if it is possible to place an object (current tank) on the map with freecam switched on to create a new tank-position.