Air bags are the way to go, I have a friend that had to do the same. I am sorry but you could not give me a Dodge anything!!
That said they all have there issues, Ford, GM, Toyota,But Dodge
i have 09 Silverado 1500 4X4, and they are to low to begin with, the Sea Ox is a heavy boat, then I have a 7000# 30' camper so what I have done to the last 3 GM's was put 3/4 ton springs in and no issues.
But you are right why did they go away from leafs? GM went to torsion bars in the front to get away from there sagging fronts, but now have gone back to coils also. So far there ok but I just turned 45,000 will see in a little more time.