RE: rudder pitch coupling
I am not sure about the terms you are using - "kicks the tail back" and "makes a turn". Could you define the maneuver and resulting action in terms that give the initial attitude of the airplane, all the inputs to control surfaces and pitching toward the canopy or belly with rudder, etc..
I don't believe there is anything inheretly bad about your setup. It could be a result of too much rudder deflection but you need to say how much you are givng also.