If you want to improve the ride on the Freightliner, suggest you consider Koni shocks. FSD on the front and adjustable on the rear. Or, adjustable on both. From my experience, Bilsteins will give you a rougher ride.
Also, if you really want to improve the way the FL handles, consider installing Henderson's Supersteer Motion Control Units. They are valves that are easily installed in the air lines at each air bag. The improvement in overall handling of the coach is pretty remarkable, IMO.
2019 Grand Design Solitude 384GK 5th wheel. Glen Allen, VA