Craig Keener's Galatians Introduction

I don't usually read commentaries from beginning to end, but it could happen with Craig Keener's new Galatians commentary. Here are thoughts on the introduction.

Introduction
I really liked his introduction and found myself in agreement with almost everything. Here are some notes:

• "Ancient authors did not always follow hierarchical outlines" (xlvii). I actually think Galatians has a pretty clear outline, but I take his point.
• Some argue that Galatians was more about "staying in" than "getting in." Not sure I agree with that.
• "Paul envisions gentile believers as spiritual proselytes." but not physical ones. Yes
• "Most scholars in Luther's day thought that Galatians abridged Paul's earlier argument in Romans, whereas most scholars today deem Romans the later, more mature work." (4) Interesting. I did not know this and the contrary seems so obvious today.
• Themes in Galatians: gospel, law, promise, Spirit. (6)
• A common median for the dating of Galatians is 51. (7) So Keener also dates it to about 50-52 (13, perhaps from Corinth then?). 
• He dates it to after the Jerusalem Council because he thinks the similarities between Galatians 2 and Acts 15 are too many for them to be different events. I agree in general. (e.g., 11)
• However, he fairly treats the theory that Galatians 2 relates to the famine trip of Acts 11. I agree with him and others like Lightfoot that the timing would be too scrunched for that.
• I personally prefer a date while Paul was at Ephesus, around the time of 1 Corinthians, ca. 54ish.
• Paul's audience is Gentile. His opponents probably Jewish. Keener favors a group of people connected with Jerusalem. (e.g., 25-26)
• He favors south Galatia. I came to agree between the first and second editions of my New Testament Survey book. Older commentators thought it was north Galatia because they only knew the classical references and early Christian commentators weren't aware of the Roman boundaries of a previous day. A large majority agree today. What clinched it for me was the common sense that Acts talks a lot about south Galatia.
• Interesting that Galatians would have filled up about half a standard papyrus roll. Two copies would have cost about 6.56 denarii or today $722.