I recently finished reading Helmut Koester’s Paul and His World. It is a collection of essays that derive from various lectures and articles throughout his life and span nearly half a century! His main interests are in 1-2 Thessalonians, but has discussions of other epistles as well. He is at his best when he is dealing with matters of epistolography, archaeology and textual criticism. One may find his theological discussions…eccentric? But, on methodology especially vis-a-vis archaeology he rightly exposes common flaws of NT scholars. In particular, he brings down Jewett’s ‘chiliastic piety’ movement of Thessaloniki.There is quite a mixture of themes and issues that K. deals with in his lifetime and so Paul is barely the unifying thread, but he does have a number of excellent arguments and statements.
If you plan on engaging in archaeological matters in your research, consult Koester. For more on this, consult my book review forthcoming in the European Journal of Theology.