I actually like the stock main pack leafs on that were in my DRW. I added to the overloads. Drives nice empty. Doesn't sag much when loaded, but I also did a progressive leaf for the overload. So that when it is loaded it's not rough as sh!t. I've built quite a few leaf packs over the years from used spring packs. From fleck off road to beefed up haulers. Overloads make sense for dual purpose ride quality. Otherwise the main leaf in a progressive pack gets bent backwards under heavy loads. Which is hard on them. But again to each their own.
Both sets of rear lift springs on this truck, including the overloads have been custom spec'd. I understand what you're saying but never have found a set of springs custom or otherwise to ride as well as the lighter stock options with bags. Throw some decent dampers on the front and rear and it doesnt need to ride like a lumber wagon.
We may be saying the same thing just politely disagreeing with the iverload spring being the solution versus an airbag for heavier towing. Or i guess loads if you put a pallet of bricks in the bed.
Most of my trucks with stock suspension are riding on the overloads, or at least the front pad, without a trailer even hooked up.
Enter the lift kits. Mine never decreased anything in terms of useage. They never sagged as bad towing, they arent as mushy turning, and obviously they helped tremendously offroad by allowing larger tires.
This truck wont see hard useage anymore. Its getting cleaned up really good and repainted. Mall crawlered to yank my enclosed trailer around. Which is why i chose 3klb rear stock springs. I dont think my tongue weight is very high. With two hands i can pick up the tongue. Its heavy, but not 1k kbs. I can pickup 600lbs on a bar and it feels very similar, maybe a tad heavier.
Ill be sure to update how it all works. I just ordered some bags yesterday.