I have a similar issue with my TC. The water tank is shifted towards the passenger side so that about 2/3 of the tank is on that side. The refrigerator and generator compartment are also on the passenger side. I have never had an issue with the extra weight on the passenger side but I do try to load any additional items on the driver's side.
The amount of list you measured is pretty small compared with the variation in road surfaces. For example, the standard road has a crowned surface that drops about 1/2" per foot or 4" for the roughly 8' width of your camper. We are so used to this, we don't even notice.
BTW, my experience with airbags was horrible. I got a lot of bounce and had to set my Rancho shocks at the highest setting to tame that somewhat. Unfortunately that high shock setting made for a jarring ride. If you really feel the need to level the camper, I would recommend SuperSprings. They can be easily adjusted to level the ride from left to right.