Pitching upside down on hard brake

I’m flying a 2014 3DR X4 in a V-Frame setup.

I am looking for advice in how to adjust PID/angle limits to avoid my copter pitching over on dramatic movements. What i mean is, while moving at a decent speed forward of backwards, the automatic braking that occurs when i release the stick is sometimes enough to flip the aircraft. A sudden pitch back while moving forward too fast does this as well. Some fast turns as well.

I had my battery to the rear slightly to offset a gimbal, but will try with it farther forward.

What would be the best place to try and limit the aggressiveness of pitch movement and the angle? Pitch axis rate controller? Putting a max on that output? I will be experimenting as I can but if anyone has any insights I’d appreciate it (flights are far between for me)

[infocopter][/infocopter]

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