Smoother Highway Ride for Coilover Conversion

[NOVA]

I have the Ridetech Coilover Conversion W/HQ Shocks,W/Truturn on A 72 Nova, its all original Ridetech components/shocks etc. that came with the Kit, nothing has been changed, I have tried some adjusting on the shocks, it does not seem to really do that much, kit has been on the car for about 3 years now, I think it is the latest/current generation, but not positive on that.

I do notice when I push down on the rear bumper for example there is very little give, very little travel ?
I am wanting a smoother Highway / Cruise ride, one thought I had was maybe a different (lighter?) spring rating OR is it shocks ?

I know there is a ton of knowledge here for some positive feedback, just looking for a few possible suggestions to accomplish a smoother highway / cruising ride for my Coilover set up.
I did do a search and found one link but it was from 2013, maybe there is some newer more current info on this subject.

Thank you