Sometimes they have another shape
Here i will just let show how other rudders looked like. Might inspire you for a cool look. But remember ...  the tail needs to stay short. Don't make a long shark tail for instance.
Construction by Jean Francois Adam
HM163 by Hans Engels. 
For some reason this HM380 got a underpart in the rudder. It now looks more like some Croses designs. Build by Chambery.
This HM14/360, build by Bernard Domont, has a quickly removable rudder. At the bottom it had a pin that slided into a opening. At the top it fell inside a U shaped metal part. This part was welded into the tube which was in fact the real rotating part. It became the hinge of the rudder. That hinge stayed always connected to the fuselage. If you unscrewed the bolt which had "side arms" and you pulled the bolt out of the rudder, you could simply lift up the rudder so the pin at the bottom came loose too and you had the rudder in your hand. Bernard Domont rolled this airplane backwards on his trailer. That was reason why the rudder needed to be dismountable.