This method is preferred over the gimbal.

Currently the uniball is mounted on the rotating mast and the stationary lower portion of the swashplate is mounted outside the ball. The uniball can rotate or not - its choice. Later look into mounting the uniball on a non-rotating inner of outer tube.

Perhaps, just let the uniball ride up and down on the rotating mast on oilite bushings.

Re 3-blade CVJ & HS Rotor: The hub spring should slightly reduce the required rang of cyclic. This may be good since I think the amount of motion of the spherical bearings is very close to that which was desired for the 2-blade teetering rotor.