I think you are adding all the LCP parts, and not just the parts that Vans recommend you to replace. I would love to see you post the list of parts that are needed to be replaced. Because I suspect you are adding all the LCP parts in your calculation.
My point earlier is you want an airplane that has zero LCP parts instead of a "safe" airplane deemed by Vans with acceptable LCP. This is where the unreasonable aspect of the argument is from. In the aerospace industry where I work, there is nothing like a perfect part. All parts have tolerance for defects, installation errors, etc. When we find them, we do the analysis and if they are safe to use, we sign them off and use them. I've had a multi-million spacecraft part that someone dropped on the floor and after testing, it worked and we flew it into space. Nobody is going to throw away a multi-million good part even it was dropped and had visible dents.
You said "The parts delivered to me did not conform to what I agreed to purchase". What did you agree? In the aerospace / aircraft work, we conform to the safe and successful operation. So my earlier comment about you just don't want any LCP part at all is still true, even if it is safe. Airplane company, kit or certify, standard is a safe and airworthy airplane. Even the airliners don't throw away parts when Boeing and Airbus deem they are safe.
There are a lot of banter about future value of the airplane. I feel for them. But that is not about engineering. It is about investment. I don't think Vans promise any future RONI, at least not to me. I know for my case, when I purchaed the kit years ago, the expectation was a very negative RONI. I never expect to recoup the cost of my RV8, ever. If I buy a house in Socal in 2006 at the peak and the price crash in 2008, the negative RONI is on me. I had my share of negative investments in my lifetime.
Now here is what I think either your fear and the unaccepting of LCP part is on the irrational side. You say you are happy to fly your Cherokee 180. I love flying it too since it is my main club rental while building. But from the engineering perspective, the RVs are so much less risky than ALL the Cherokees, because, the Cherokee wing spars are known to CRACK and people had died when they failed. It was so bad that the FAA was close to mandate all the Cherokee wings to be removed for inspection. Your N8ML is basically flying on borrow time because fatigue will eventually affect the wing spars. All it takes is time. I know the mandate inspection when it's 6000 hours and above. I may not have the numbers exact but yeah, given a choice between flying a safe RV with LCP parts, versus a 50 years old Cherokee N8ML with known deadly defects, I take the RV.