The nexus 6 screen although QHD isn't as good as either the S6 or 6+. Its a good screen but its noticeably dimmer and suffers from yellow tint without you manually compensating for it.
This is the only thing I disagree with in your post. The Nexus 6 is ~500 ppi while the iPhone 6 Plus is ~400 ppi. I think its screen looks better than the iPhone's. It is dimmer, but I rarely ever needed to use my iPhone at full brightness anyway.
I'll add some input. I think the camera is just as good as the iPhone camera in most conditions. Only in low light is the iPhone noticeably superior. Battery life isn't as good, but it will probably get you through a full day. And there's quick charging and wireless charging which are very convenient.
I don't really miss Touch ID that much. It was nice to have but I find the pattern unlock very easy, and you can also use things like trusted voice, trusted face, trusted location, or have the phone automatically unlock when it's near something like an Android smartwatch.
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If you're looking for picture examples, go to
http://reddit.com/r/nexus6. People often post pictures taken from their phones.
I went kayaking over the weekend and brought my Nexus 6 and got some great shots. I might upload them a bit later but I would say they're just as good as what I would have taken on my 6 Plus, although the picture captured more detail due to there being more megapixels.