"The rotor system is capable of handling large 59 pound tip weights. The lack of bearings and over-stressed bolts make this an attractive helicopter rotor blade idea." Look into the method that is used.

To reduce the vertical dimension of the rotorhub consider replacing the axial pitch bearings with a 3-blade tension-torsion strap. This should result in a slight reduction in the obliquity.

The following talks to the possibility of an aerobatics helicopter. The unloading of lift on teetering rotor heads can cause mast bumping and on articulated multi-blade rotor heads it can cause droop stop bumping. This cannot take place with a absolutely rigid rotor head.

Might the absolutely rigid rotor configuration be unstable in conventional flight and stable in inverted flight? Note that inverted flight will put the tail in the rotors' downwash.

Consider using the composite fuselage as the static mast. Assuming that the rigid rotor has less vibration, then why mount the rotor to the drive train and then mount the drive train the fuselage. The drive train plus engine have their own mounting to the fuselage.

Consider manufacturing the hub out of composites.

There might be sound reasons, such as weight and design, for going with elastomeric bearings from the beginning.

The increase in the weight of the helicopter due to having a rigid rotor will be quite high. Is there any way of reducing this weight somewhat by producing the hub out of composite material?