What Should I Do To "Soften" The Ride Of New Air/Nitrogen Shock Absorbers?

[CarefulRider]

With a view to softening the ride of my 2007 LB150T-12, SUNL ADVENTURE 150cc scoot, I just put on new nitrogen-filled shock absorbers. To my dismay, the ride is harder than the conventional absorbers that I just took off. The spring pre-load adjustment is all the way up to the top of the adjusting threads, so if I did any threaded adjustment, it would be "down" the threads, thereby compressing the springs. I don't think that would yield a softer ride.

I checked the pressure in the shock absorber cylinders: one is 26 psi & the second is 32 psi.

I have read that I can expect a rather soft ride with this type of shock absorber. What should I do to acheive this soft ride?