2015 Chevy Silverado 2500HD, Improving Unloaded Ride

Aired down to 55 front and 55 rear does make a good difference. Crazy harshness is gone--lets say it went from a 10 on the harshness scale, to a 7. Sulastic kit and adjustable Rancho 900XL's go on next week. I am also going to throw in a few hundred pounds of ballast in the rear. I was thinking it would be nice to carry the ballast in water and will do so if I can think of a good way to do so without spending too much.