Outstanding! Sounds like you all had a great trip! I'll take a moment and answer Question 1.
I too have a dually (F350). On my first few camping outings fully loaded I noticed some left and right rocking too. I researched the issue and I ended up installing four "supersprings" on the frame/suspension back in 2013. When loaded, and they have some weight on them, they provide some good cushion and stability. I've been quite happy with them and would say it corrected 90% of the problem. There might be some even better options out there now - I don't know. Happy Camping!!