If it's a really cool, experimental and unique song I am ok with a lot less than what I'd expect if it's a rather state of the art dance bop (let's say, as in GH as opposed to BTW).
Yeah. If she does at least 70-75% of what she did with BTW overall she'd be good. If she manages to outdo BTW by a significant margin she'd be exceeding the expectations.
She's not coming off of a huge era like the last time.
How she does in the US will depend greatly on whether radio drops the ball or not. Radio tossed Born This Way in the trash can almost immediately after it hit number one on Pop Songs, which contributed to its lack of sales longevity.
It is possible for her to open with a million again. As long as the GP take to the lead single and are intrigued by the app she'll have the million+ opening sales in the bag