Will Air bags make a big difference?

So we've had a 21'5th wheel for 16 years, and love it, but it's getting long in the tooth, and it's a little small, so we bought a 2012 Shasta Revere BH, 27', 31' with the hitch. We took it on our first trip this past week and had a real problem with the truck bucking up and down and also swaying. It's 5777 dry weight, and our Chevy is a half-ton, rated up to 9400 lbs. Anyway, we made it to our destination, but I felt so uncomfortable driving it do the swaying and shaking. The camper came with an old equalizing hitch, but not sway bars, the owner said he had never felt he needed them. I called a local hitch place and had them install a Curt hitch with integrated sway control, and thought we were all set. It DID help a little with the sway but didn't seem to help much with the bucking. Any little bump we went over the truck bucked up and down and, and the steering wheel felt like the truck was over loaded. I called the hitch dealer back and he said I probably need to have airbags or something else done to strengthen the suspension. My question, would that make a huge difference? My wife says she can't ride in this truck if we can't solve this problem as the bucking and vibration makes her sick. Mind you, we've been across country several times with the 5th wheel. We had occasional bucking with that, but only when we went over severe bumps like a bad bridge transit for example. I've got $700 invested in the hitch, with little to show for it, and the airbag would cost about $1000. Well worth it, if it works, but not if it only makes a little difference. Your thoughts would be appreciated. Thanks!