Going back to the first post I think you mentioned there was no upgrade done to the rear springs? If you want to eliminate that sag Id recommend the land rover 9449 coils. I think you should be able to get them shipped there and they seem to just shrug off the weight of anything short of a boat.
I was fully loaded for my last trip with at least 500 lbs counting two people, two pets, two full sized spares, 5 gallons of spare gas, 7 gallons of water, a trunk full of tools and spare parts, coolant, atf, oil, power steering fluid, plus 3 suitcases and a large metal framed backpack on the roof. And the 9449s only compressed about an inch. So the truck ended up riding perfectly level and handled the moab trails without even getting close to bottoming out. The coils make the ride a little rougher when you’re low on weight but I don’t really mind it at all, I think it gives it better handling characteristics anyway
I don’t have any experience with airbags but I’ve heard people say that they are a bit of pain and will eventually fail whereas the 9449s will probably outlast the truck