I had the same thought myself , but I gotta admit , one huge negative instantly popped into my mind ;

Unless you had multiple cameras , and were able to toggle the view behind you and then again back forward in less than a blink of an eye , you would be hobbling yourself greatly in RC combat . If your view is forward only , or even forward and somewhat to the sides with a panoramic style lens , you can't see what's most important , that which is on your tail . Standing on the ground directly viewing the models gives a complete view of all the action with no blind spots and it makes the battle all the more challenging in that no one can come up from behind unseen .

Even if direct eyesight holds an advantage , for now , , , It's still a cool thought to do FPV combat .