A 29% pivot point is unstable!
The surface will seek one extreme of its possible movement or the other, and may oscillate between the two, if the servo gears don't strip which is probably what will happen with any mini plastic- geared servo.
The pivot point MUST be no further back than 25% to maintain control of the surface.
A small amount forward of that will provide some degree of streamline centering.
Also a full-flying tail has -less- authority than a hinged surface.
It stalls at lower Cls than the conventional type.
The full-flying style is more suited to planes which don't manuver a lot; TD, electric gliders... something where trim drag makes a difference in the end performance.