To be clear, I'm not trying to say that there are no issues present. I think the overly aggressive noise correction is a problem, and I'm not really sure why they decided to go that way. I don't see any basis for claiming that the problem is too much compression since A) the files themselves aren't actually any smaller than previous phones and B) the issues we're seeing don't resemble compression artifacts at all (at least not to me). They're clearly caused by noise correction.
My main point is that when I look at photos taken with my 6+ without zooming, either on my iPhone/iPad or on my computer, they look very good overall, and noticeably better than the iPhone 5. If I went zooming in to look at all the fine detail, it might be different, but that's not what I require of my cell phone camera.