Here I am....
I removed leafs from my rear springs too. I made a huge difference. Shocks will not soften the ride, but will help the side to side sway.
I have looked into air ride. Hendrickson makes an air ride that I was quoted between 6k and 8k installed. That would make a huge difference.
Hendrickson Medium Duty - Bus - Motorhome Suspension Systems
noise can be minimized by some different things:
1. sound decoupler under the floor
2. sound absorber in the dash
3. padded leather cover over shifter
4. sound isolator on the doors
The Freightliners drive much better than the Internationals, but they are noisy. I looked hard to find a Cummins instead of a Cat, because the Cats are usually louder.