Leaf pack recomendations

I am currently running an Icon 3 leaf pack and my truck drives like a dump truck. The ass end is constantly bouncing around. If I load the bed with 400 lbs it rides a lot smoother. I know its not the drive shaft angles causing it because I'm running the stock driveshaft modified with a double cardan joint. I'm guessing for the $250 I paid, the leaf pack isnt very good. Any recommendations on brands of leaf packs that would ride smoother? I rarely carry more than 200lbs in the bed at any time. My setup is 2005 Sr5 4x4 short bed, 2.5" headstrong springs w 5100s,freedom offroad upper and lower control arms up front . 2" icon 3 leaf pack without overload leaf installed, 5100s

 

Alcan, Deaver, Archive, Dobinsons, Icon, etc. all make full leaf packs that might suit your needs.