don't reinvent the wheel doing the fowler flap action... for small planes at slow speed, the control horn makes a fine flap hinge.

You can change the rrelationship of kick-back to angle by moving where the hinge line is fore and aft compared to the retracted flap LE position. furhter back hinge = more kick-back of the flap. further down = more kickback. (for the same angle of deflection) The hinge line being further back would ALSO induce the front of the flap to rise. (useful when making flaps act as airbrakes at 90 deg deflection in a sailplane.)