Benefit of two cams is two different angles. What you want to see in footage isn't always what you *need* to see while flying. If you mount the gopro on the LE, it'll look like you're flying free, superman style -- nice, but not always handy for piloting. you can then mount the FPV cam farther back on a pan/tilt. This will allow you to pan around with a head tracker or dial for better orientation or spotting.
Putting the main cam on it's own pan/tilt can work, but you almost need a cameraman running that rig while you pilot.
Think tank crew -- driver can point the tank in any direction, but the gunner can shift the turret independently to keep aim. one man (a camera for this analogy) can't do both well -- or at all in battle -- because they're different tasks.