The 2008 and later Gulfstream Independence was built on the Freightliner MC chassis, which has leaf spring suspension rather than air and a front engine. Converting to air suspension is probably not financially practical, but I suppose auxiliary air bags could be added, just like they can on any leaf spring gas chassis, truck or car. I doubt if it would do anything for the ride, though.
The Independence is very much an entry level diesel coach, so I would not expect any of the nicer attributes, in house or chassis. My guess is that you will be looking to trade up before too long.
2004 American Tradition; 2014 Buick LaCRosse
Homebase in the Ocala Nat'l Forest near Ocala, FL