The basic trim pressure you feel flying your gyro comes mainly from the amount of gimble offset and to a lesser extent the blades used. (High performance blades like Dragon Wings or Sport Rotors require more spring tension than Bensen blades.) Most heads have about 1" offset. Reducing the offset lessens the trim spring tension required, while at the same time reduces the stability the offset provides.The head isn't visible in the pics, but, with an electric set-up there is also the possibility the failed trim actuator caused it to require more back pressure. If that's what happened, you may need to redesign the electric trim so that can't happen. You could use a long trim spring from the torque tube to the mast that partly compensates for the offset, along with the electric one to add both redundancy and adjustability. If either one individually failed, you would still have partial compensation.
Hang testing is mostly about control centering and doesn't have much, if anything at all, to do with trim pressures.