I am in the same (kind-of) boat as you, in fact I have two posts in this forum so far, the first one Quality of new... sigh...
echoes basically your general concerns.
My second post All I have to say is wow...
was after I went down to my closest Airstream dealer and spent hours looking over their 20+ units of all types.
I did not do a low level rivit check, but I did do some serious looking for QA/Design issues, and I did find some minor stuff but nothing like what you are saying, they all seemed solid. Way better then the SOB's I have looked at over the years.
For me I am now on the path to become an AS owner, and have settled on trying to find a newly used AS, but if I get a few months down this path with no luck, I am going to order new b/c I have an 8 year old daughter and we are going to be RV'ing next summer in an AS god willing. My time with my little girl (vs teenager, grownup) is shrinking fast, I will never get it back, this is what is driving my process, for what it is worth. :-)
Unlike you I have never owned an RV, so take my comments in the proper context which is a noob, e.g. my comments all need to have the noob bit &'d into their context, if that makes sense.