Your email was fine... for a minute. But the end result? Credibility shot-to-hell.

You had a legitimate concern, then resorted to the "piling on" of other irks. IMO, it really wasn't that big a deal to be so up about. But there are effective ways to complain. There is an art to it, in fact. But all too often, I see people blow otherwise valid complaints by going overboard in presenting their case.