Firefighter701......I just sold my 2005 Diplomat that I bought new. There are several things you can do your chassis. The biggest/best improvement will be the shocks. DO NOT put the Bilsteins on it. They were designed to be installed with a ride enhancement kit (REK) and won't work as well as the Koni's. Buy the Koni FSD's. You should put all eight on, but that can be a big bill all at once. Do the fronts first.
They're very easy to install if you have air tools. Still easy if you don't but will take a little muscle. Turn the wheels hard right and you will have easy access to one on each side. Turn hard left and do the other two.
Another very important aspect as to how your coach will ride is tire pressure and ride height. If your ride height isn't adjusted correctly, your coach will actually ride rough. You have one ride height valve on the front and two on the rear. They're easy to measure and adjust. Lastly, get the coach weighed and put the correct amount of air in your tires.
If you do the above, two which are free, you'll eliminate the short chopping ride you get on rough roads.