I use the R-Sys wheels (fantastic by the way), they are very stiff yet quite comfortable as long as I don't put too much pressure in my tires. I have Michelin Pro2 Race that have a recommended max of 116 psi. I weight 175 lbs and found that 105 to 110 psi is a great sweet spot. Above 110 I find the rear a bit too harsh. At 165 lbs I would probably recommend 100 to 105 psi.
Try you current setup at a lower pressure, it might make a big difference.