I agree with you on the 1st paragraph and disagree with you on the 2nd.The Nexus One was not cheap. The Nexus S was not cheap. The Nexus 6 ain't cheap. So half of them have had normal prices, while the other half have been lower cost. That does not say anything definitive either way. I already quoted Sundar explaining what the Nexus program is. This whole "Nexus = cheap" definition was created by fans, not by Google.
I predict they'll sell more of the N6 than the 5, because it will be on all carriers. We've all wanted stock Android to reach more of the people, well this is the way to do it.
An even better way to do that is make a phone that costs $200 less which would mean that it would be free with contract on US carriers. Cut as much or sacrifice whatever you have to reach that "free with contract" price goal.