Everyone should check their autolevel regularly, the can and do get out of calibration. We see this happen several times a year. dont put blind trust in technology, no matter how many years its worked fine.
Best level is a frying pan with a bit of water. Place it where you can see it then manually level. The water knows all 4 ways, cannot be wrong.
Tires off the ground front or rear is never the best idea, whether front to rear or side to side. Never have seen damage because of it though, it just makes sense particularly with the rear axle due to its braking, weight hanging on suspension and differential stability if one side is off the ground.
In my opinion the best campsite is level side to side, 2-3 inches low to the rear.
Drainage is a must, noone likes a puddle. Trailers lower in front gives more stability due to the shorter jack length, for A MHs the steps are not lifted, for Cs they are often high at the rear being built on a truck chassis.
Ever notice Cs without jacks nearly always have blocks under the front wheels when parked on a level site?
No mfgr I know of advises to not lift the wheels off the ground, tire shops use levelers to change tires. What are you comfortable with?