As far as I'm concerned, it's all about tire size and tire pressure. Not worth changing your tire size just for that, but the larger the tire and the smaller the rim diamerer the more rubber you have to flex and the better the ride. That being the case, I drop my pressure till I have a good bulge in the sidewalls. Then vary the speed till the ride is less worse. I've done a lot of talking with the major tire companies, and their only concern with doing that is heat buildup from sidewall flex. The lower the pressure, the lower you need to keep your speed. Just get out once in a while and put your hand on the sidewalls. Warm is fine. If it starts to burn your hand, that's too much heat. You also increase the chance of sidewall damage on offending road objects and rolling the tire off the rim. But, in many years of reducing pressure (I usually end up with 20-23 psi on the SMB) I've never hurt a sidewall or rolled a tire.
Just my methods - use at your own risk