One of the misunderstood items in the RV world is tire pressure. Get the specs on your tires, weight your rig, and then set tire pressure accordingly. Most shops just air the tire to some very high number (ignoring weight) and then the tires are like riding on bricks. Of course, tuning tire pressure is not going to perform magic but it can make a difference in ride 'harshness.'
Probably worth noting... weighing is a pretty simple process and can be done at many truck stops (CAT scales), some country co-ops, and probably many other places. At the truck stops, you just pull onto the scale (make sure front tires are on front 'pad' and rear tires on rear 'pad' and use the intercom to get the attendants attention. They ask for truck number, just tell him #1 or your favorite number, then park and go inside. Tell the counter person that you have a weight slip and truck number. Costs something like $10. You then have the weight on your front and rear axles.