Researching dealers is what I did as well.
I now go to a dealer that's 30 miles away when I could go to one that's 7 miles away.
They are all franchises as far as I know and some care and some don't but to get crap from Suzuki head office is not on.
I tend to agree with this. Unfortunately, from the content of your letter to Suzuki USA, it appears that most, if not all, of the damage was done by the dealer. Having seen the condition the bikes come in when crated, I'd also lay the problems you attributed to Suzuki fit/finish/quality on your dealer's doorstep as well.
That being the case, I think it's unreasonable for Suzuki to eat the cost of damage done by the dealer or to rectify modifications that you undertook on your own accord. While I would hope that they might assist and mediate any resolution discussions you might have with the dealer once you have exhausted all avenues w/ the dealer yourself, it doesn't sound like you had gotten to that point yet.
From your letter it sounds like most of your interraction w/ the dealer was with the service director and the tech staff. What I would have done was compose a letter and make phone calls to the shop's GM or owner. Give them the opportunity to make things right and when that's been exhausted, provide Suzuki USA with all documentation (not just your letter above, but all work orders, responses from the GM, etc).
I purchased my bike from a dealer that's 70mi away from home and plan on letting them do major service rather than the biggest dealer in the area (just 5mi from home) because they have a much better reputation in the both sales department and service department. How do I know that? Research, word of mouth from friends (who have bought multiple bikes there and had them services), and experience (I brought my old SV there a few years ago and found them to competent, transparent, and fair. I realize that buying a bike isn't the same as buying a car because typically the dealer network is much smaller, but you always have choices.
Good luck and I sincerely hope you get the many problems resolved to your satisfaction.