I'm kind of upset my Deavers have essentially leveled-out already—especially when I haven't really done anything in the bed yet. This is one area I realized I hadn't planned-out very well. I still expect a few hundred more pounds once the removable rear platform, fridge, auxiliary fuel tank, water, camping gear, RTT, awning, spares/parts & emergency gear are all on-board.
I've learned too much spring could give a stiffer ride. I've been told too much shackle could put too much strain on the springs and offer less up-travel—but more down-travel. The benefit to shackles, however, is a level ride, fully loaded.
I was concerned about the uptravel limitation, but I'd rather sacrifice a little uptravel for a smoother ride. Ultimately, I chose a set of 2.5" All-Pro shackles. I'll be avoiding airbags due to reliability and maintenance issues. Later, I'll upgrade to a 10 or 11 pack.
Still ready for the rear cross member...