Years ago when I was getting started in this mad hobby, a gent by the name of Bob Palmer wrote an article about flying stunt. He wrote about the experiments he ahd done on various planes. Like flying a Chief with a .19 size engine.
He made a statement in the article about rudder offset. He had a plane that was flying good. During the day he knocked the rudder off. He stated he was amazed at how well the plane started to perform. But, then the engine quit and he stated that is when he noticed the difference of the rudder not being there.
As some have stated already, make the rudder adjustable. Also don't forget all the other stuff like, adjustable leadouts and weight box on outboard wing. Don't forget the fuel tank. It all depends if you want to get a plane that will fly and do what it's supposed to do or just fly a rock on a string.
Have fun, that is the important thing. DOC Holliday