Most servos can travel 120 deg, 60 deg in each direction. Just because you can turn the servo arm by hand further, doesn't mean the servo's internal electronics will support more than 120 deg.

I'm not quite sure what you meant by "I set my arm up for a 1 to 1 ratio", but if you mean the linkage connections on the servo arm and at the control surface are the same distance out, that is not necessarily optimal. Shorter at the servo and longer at the control surface gives you better mechanical advantage. In your case, I would dial the travel back to 135 or so (so that you have travel left for your trim levers to use) and set up my high rates (dual rate at 100%). You will have to move your linkage in on the control surface and/or out on the servo arm to achieve the throw you want (as opposed to dialing up the travel). Although you'll lose some mechanical advantage by doing this you can probably go to a higher torque servo if you experience blow back in flight. Then I would set my low rate throw by dialing down the dual rate percentage.