A coax has the real need to avoid self-midair collision, so the mast height and disk separation is a big term in the design equation. Also, the designer will often make the two rotor have different hinge offset (lowe has more) because of flapping and also mast moment considerations, where the long mast runs up to the lower offset rotor head.
Grav, the s-76 has elasotomeric bearings and is a conventional articulated system in that respect. Its hinge offset is about 4%.
I corrected my previous post to make it match the S76 (it was hypothetical, previously).