RE: question on airplane balance
If an elevator is very far from neutral, it could mean some trim issues. How much down trim did you add? Does the down trim manifest itself in too steep of a landing glide slope (is power on/off trim the same)? Another helpful test is knife edge to note if there is a pitch couple. Does the down trim cause a tuck to the gear? Remember, in knife edge, the elevator is gravity neutral and if it is trimmed to compensate for out of balance in level flight, it might display an unwanted characteristic in knife edge.