I have a Class C built on the Sprinter Chassis. It's another brand but thought members here might be interested in at least reading about the major upgrade I recently made in changing the seats to high end air suspension seats. They solved both the problems of poor comfort and the seats being too low when turned.
We now have very comfortable recliners when camped that are the correct height and a comfortable seat with air ride while underway.
These seats made such a huge difference for my wife with severe back problems that I posted a fairly extensive blog on them.
Sprinter Seat Upgrade