My Monaco coach on the W22 chassis has over 80,000 miles and I don't feel that my springs are worn out. I still have a gap between the rubber bumper and the frame. I agree that I also prefer the aluminum sidewalls to the fiberglass and the aluminum peaked roof is strong enough to dance on.
Are the awnings still over the slides?
Since the tires are worn on the outside there may be a problem with the tie rod ends that is allowing the tires to scrub down the road. You should be able to lift the front tires off of the ground with the leveler jack and see if there is any looseness in the front end.
Are there any small bubbles in the paint?