I have a thread in the expedition section called storage - there are some really good ideas in there. Post your solution in there.
I bought a cheap roof tent when I got the 110. Decided it was a faff and sold it. Yes, there is a clear advantage to having a ground tent as you can simply drive away. Five years later I invested in a second hand quality roof tent with awning and annex. Would not go back to a ground tent again. The set up depends on what you want to do once at a camp site; we tend to only stay for a night or two.