RE: balancing a full flying stab
In balance is best. If not in balance then there is a constant load on the servo to hold it in position and the servo will be buzzing and drawing current. The weight of any imbalance is proportional to the G load so if the servo is having to hold against a weight of X ounces in level flight then it has to hold against a load of 6 times X ounces in a 6G turn/loop, so what may be a couple of ounces of pull to hold it in level flight becomes almost a pound of pull from the servo in a 6G loop, just to hold the weight imbalance. Also any imbalance can come as flutter when the plane is disturbed by gusts and turbulence which is why many full size have mass balances on control surfaces - if you shake the plane up and down a balanced surface stays level giving no flutter or load on the servo, if the surface is not balanced it will flap about causing a load on the servo and flutter if the frequency hits the right rate.