Again, this is coming from somebody who doesn't even particularly like Boston all that much.
Well, if you want to redefine 'city', then fine. But Boston has as many people as Sydney Australia, and I'd definitely consider that a major international city. One of the best in the world actually (8 years living there).
Boston pricing is out of this world to be sure. More expensive than NYC the last I checked. A lot of that is do to increased demand, which goes against your first point a bit.
But you do get way more there. Given similar cost in rent, you might have a small apt in Boston, but you are getting a shoe box in NYC.
Tell that to people around the world who flock to Boston for educational purposes. It's probably number one in the entire world as far as education/research goes. And growing in terms of companies/incubators that contribute to or benefit from those research hubs. It's a great walking city too. Comparatively beautiful.
Philly above Boston? hahahah Philly is a crap hole. That's coming from someone who was born there, and entire family still lives in DelCo. Seattle? Ask
@FriarJ. I personally like Miami, so no comment. Wouldn't really want to live there, but I like it.