Suggestion 1: Fuselage "Twist" Property:

In the fuselage editing box there would be a new slider below the fuselage block size and corner selectors, that when moved would twist one end of the fuselage. You can twist left/right sides or front/back. Range from -360 to 360 degrees. Maybe a little button above the slider as well to choose which side to twist. This would make complex shapes an absolute breeze in the game, such as wings and stuff.

Suggestion #2, Left/Right Scaling:

Allows you to change the size of the left and right sides along with the front and back. Again, more possibilities with complex shapes.